I've been doing endurance testing on microSD cards for the last 3 years. Here's what I've found.

[u/mikaey00]

Hello everyone!

I posted here last year, but that was last year. It's been a whole year (and some change) since then -- not to mention it's now the 3-year anniversary of when I started this project -- so I figured it was time to give you an update on my microSD testing project.

Before I dig in, a shameless plug for my Patreon.

Next, some quick stats:

• I have a total of 351 microSD cards in my collection -- spanning 111 models across 52 different brands. Of those:
  • I've tested 177 of them to the point of failure.*
  • I have 107 of them in testing right now.
  • The remaining 67 are sitting on the shelf, waiting for one of my card readers to free up.
• These cards have endured over 133 petabytes written.
• I've completed over 4.6 million program-verify-erase cycles on these cards.
• Breakdown by brand status:
  • Name brand: 163
  • Off-brand: 91
  • Knockoffs: 30
• Breakdown by authentic flash (a.k.a. not fake flash) vs. fake flash:
  • Authentic flash: 246
  • Fake flash: 35
  • Unknown: 3
• Breakdown by size (authentic cards only):
  • 128MB: 3
  • 4GB: 6
  • 8GB: 23
  • 16GB: 15
  • 32GB: 96
  • 64GB: 68
  • 128GB: 36
  • 256GB: 4

* A card is considered "failed" when either (a) it stops working completely, (b) it makes itself read-only, or (c) at least 50% of the sectors on the card have experienced verification failures.

Ok -- so who makes the most durable cards?

Because of the variety of cards that I have, it's hard to come up with a system that produces a definite answer here. Some of how I ranked these brands is going to be based on vibes. But...to try to narrow things down, I've grouped my cards into three groups:

• Industrial-grade: Cards that are specifically labelled as "industrial" or have "industrial" in their name. These cards typically come with a datasheet that includes an endurance claim.
• High endurance: Cards that are labelled as "high endurance" (or some similar wording). Manufacturers don't always put out datasheets for these cards, but they generally still make an endurance claim on the packaging.
• Consumer-grade: Basically everything else.

Consumer-grade cards:

The average consumer-grade card has lasted about 10,000 program/verify/erase cycles (so far).

1. PNY. I have 10 of their consumer-grade cards: 3 PRO Elite Prime 64GB's, 3 Premier-X 128GB's, 3 Elite-X 64GB's, and one Elite 32GB. (I have 4 more of the Elite 32GB's that are waiting to be tested.) They've gone for an average of 643 days and 15,700 program/verify/erase cycles. I've written about 11.5PB to them in total. And with the exception of the one Elite 32GB -- they're all still going strong. On top of that, the PRO Elite Prime boasts some impressive performance -- every measurement I took was in the top 10% of all cards I've tested so far.
2. Kingston. I have 12 of their cards in this category -- 6 Canvas Go! Plus 64GB's (3 of the SDCG3's and 3 of the SDCG4's) and 6 Canvas Select Plus 32GB's. They've been going for an average of 694 days and about 23,500 program/verify/erase cycles. I've written about 11.6PB to them in total. The three Canvas Go! Plus 64GB (the SDCG3's) have all failed -- but the others are still going strong. The Canvas Select Plus's in particular have been troopers -- they're among the oldest cards in my collection, and they've been going for the better part of the last 3 years now (with no signs of letting up). Additionally, the Canvas Go! Plus 64GB's (the SDCG4's in particular) boast some impressive performance as well -- every measurement I took was in the top 7% of all cards I've tested so far.
3. Delkin Devices. I feel bad ranking Delkin so low on this list, because they've endured more data written to them per card, on average, than any other brand in my collection (in the consumer-grade category). The only reason I didn't rank them higher is because I only have one model -- the HYPERSPEED 128GB (of which I have 3). But they've done pretty well: they've lasted an average of 662 days and about 13,500 program/verify/erase cycles. I've written about 5.1PB to them in total. As a side note, these cards also got the highest random write speeds of any card I've tested.
4. Lexar. 3 cards dead, 5 still going. I have 3 Professional 1000x 64GB's (2 made by Micron, 1 made by Phison), 3 Blue 633x 32GB's (made by Longsys), and 2 E-Series 64GB's (with 3 more waiting to be tested). For those not in the know, the Lexar brand was sold to Longsys in 2017 -- and surprisingly, the Longsys-made cards are holding up better than the Micron-made cards. Overall, the Lexar cards have survived an average of 684 days and about 15,800 program/verify/erase cycles. I've written about 5.8PB to them in total.
5. Samsung. 3 cards dead, 7 still going. I have 3 EVO Plus 32GB's, 3 EVO Plus 64GB's, 3 PRO Plus 128GB's, and 1 P9 Express 256GB (with 2 more waiting to be tested). Of those, the three EVO Plus 32GB's and one of the PRO Endurance 32GB's are dead -- the rest are still going strong. Samsung's cards have lasted an average of 553 days and about 11,100 program/verify/erase cycles so far, and I've written about 7.2PB to their cards in total.

• Honorable Mention: Amazon Basics. I have four of the Amazon Basics 64GB's -- and they're all still going. They've been going for an average of 788 days and about 16,600 program/verify/erase cycles. I've written about 4.2PB to them in total. I honestly didn't expect Amazon Basics to be one of the top performers when I bought them...and yet, here we are.

High endurance cards:

Keep in mind, I've got less data here -- I had 237 cards that fell into the "consumer-grade" category, but only 30 that fell into the "high endurance" category. But here's the thing: they haven't really proven themselves to be significantly better for endurance than a lot of the cards I listed above -- in fact, in a lot of cases, they've been less reliable (and generally worse for performance as well). So keep that in mind as you read through the list below:

The average high-endurance card has lasted about 14,000 program/verify/erase cycles (so far).

1. TEAMGROUP. I don't feel great about putting TEAMGROUP at the top of the list for a couple of reasons. First, I only have two of them in testing at the moment -- someone sent me a 5-pack of the TEAMGROUP High Endurance 64GB's, so I have 3 more of them waiting to be tested. Second, one of them started having issues with bad sectors right out of the gate, and has continued to do so ever since. (Those bad sectors only make up less than 0.001% of the total sectors on the card right now...but I still don't like it when a card starts to have issues like that as soon as you start using it.) But the data doesn't lie -- they've survived, on average, 404 days and about 17,300 program/verify/erase cycles, and they're still chugging along. I've written about 2.2PB to these cards in total.
2. Transcend. I have 3 of the 350V 64GB's -- and they're all still going strong. They've survived an average of 760 days and about 17,000 program/verify/erase cycles so far. I've written about 3.2PB in total to them (mostly due to their mediocre write speeds).
3. SanDisk. I have my issues with SanDisk...but again, the data doesn't lie. I have 7 SanDisk cards in this category: 3 High Endurance 64GB's, and 4 MAX ENDURANCE 32GB's. As of right now, all 3 of the High Endurance 64GB's and all but one of the MAX ENDURANCE 32GB's have failed. They lasted an average of 452 days and about 16,200 program/verify/erase cycles before failing (with the MAX ENDURANCE 32GB's lasting about twice as long as the High Endurance 64GB's). I've written about 4.7PB to these cards in total.
4. Samsung. Samsung's position at the bottom of this list has less to do with how reliable their cards are and more to do with how poorly their high endurance cards perform, particularly on sequential write speeds (relatively speaking). I have 3 of the PRO Endurance 32GB's -- one has failed, the other two are still chugging along. They've lasted an average of 822 days and about 18,800 program/verify/erase cycles so far. I've written about 1.8PB of data to them in total.

Industrial-grade cards:

Keep in mind, I have even less data here. Industrial cards are expensive, so they make up a much smaller portion of the cards I've tested: just 15 in total (so far). But on the upside -- there is sufficient evidence here to say "in general, industrial-grade cards do last longer than consumer-grade cards (and, by extension, high endurance cards)".

The average industrial grade card has lasted about 122,000 program/verify/erase cycles (so far).

1. Kingston. I have 3 Kingston Industrial 8GB's; of those 3, only one is still going. But they've been troopers: they've lasted an average of 779 days and about 141,600 program/verify/erase cycles. I've written about 3.4PB to these cards in total. (Only one consumer-grade card has come close to this number: I have one Hiksemi NEO 8GB that has lasted for about 143,800 program/verify/erase cycles so far. No idea how.) These guys do pretty well on performance too, especially write performance: their sequential write speeds are in the top 9% of all cards I've tested.

Who makes the worst cards?

There are a bunch of no-name brands out there. They're not hard to find. I'm not going to talk about them here -- I'm going to focus on brands you're likely to have come across.

Consumer-grade cards:

1. onn. I picked up four of their 32GB cards at my local Walmart -- and they were terrible for endurance. They only lasted an average of 40 days and 1,400 program/verify/erase cycles (or about 40TBW), with the best one of the four not even making it to 1,900 cycles. On top of that, every performance measurement I took came in the bottom half of all measurements I took.
2. ADATA. I picked up 3 of the Premier 32GB's; they only lasted an average of 236 days and about 2,350 program/verify/erase cycles (or about 74TBW) before they quit working.
3. Gigastone. I have not been impressed with Gigastone. I have 11 of their cards -- 6 Full HD Video 32GB's, and 5 4K Camera Pro 32GB's. They lasted an average of just 114 days and 4,845 program/verify/erase cycles (or about 133TBW) before they quit working.
4. Micro Center. I purchased 5 of their 64GB cards; they only lasted an average of 116 days and 3,421 program/verify/erase cycles (or about 214TBW) before they stopped working.
5. Silicon Power (a.k.a. SP). I purchased 9 of their cards -- 3 Elite 32GB's, 3 Superior 128GB's, and 3 Superior Pro 128GB's. Not a one of them made it to 4,000 program/verify/erase cycles before failing -- they came in at an average of 159 days and about 2,350 program/verify/erase cycles (or about 252TBW) before failing.

• (Dis)honorable mention: SanDisk. SanDisk represents the single biggest brand in my collection: I have 28 of their cards in this category (with 4 more on the shelf waiting to be tested). It's telling that of those 28, only 5 are still going (and one of them is in its death throes) -- especially when cards from so many other brands have far outlasted them. Many of them have died under circumstances any other card would have handled just fine -- a problem I've written about on my blog before. They've lasted an average of 384 days and 9,404 program/verify/erase cycles (or about 566TBW) so far.

High endurance cards:

1. Integral. I bought 3 of the Security 32GB's; the only managed to last an average of 100 days and about 5,600 program/verify/erase cycles (or about 173TBW) before failing. To be fair to them, the package did make an endurance claim that works out to about 2,850 program/verify/erase cycles -- and they did manage to almost double that. However, they didn't hold a candle to many of the other high endurance cards that I tested.
2. Kingston. This one was truly a surprise -- I bought 3 of the High Endurance 32GB's, and they only lasted an average of 143 days and about 8,300 program/verify/erase cycles (or about 258TBW) before failing. The product packaging didn't make an endurance claim; I had to hunt around on Kingston's website to find it. Their claim works out to about 5,100 program/verify/erase cycles, which they did manage to beat. But again, so many other cards managed to last so much longer -- hell, so many other Kingston cards managed to do so much better -- that I was surprised and disappointed when these failed so early.

Industrial-grade cards:

1. SanDisk. I bought 3 of the Industrial 8GB's. They only lasted an average of 234 days and about 20,000 program/verify/erase cycles (or about 160TBW) before failing -- and the only reason they lasted that long was because I let my program trudge through an nearly-unending string of I/O errors for months on end -- before they finally just gave up the ghost.

So yeah...that's all I have for now. Feel free to ask questions (although I'm at work at the time I'm posting this, so I may not have time to respond)!

Attached: pictures of part of my setup. Also, dog tax.

[u/PrepperDisk]

Incredible effort, cost and dedication.  This is impressive work. Thank you for doing this.  

I might suggest a simple visual or summary to present this information more succinctly.  As it stands it is quite thorough but a lot to take in.

[u/ExpletiveDeIeted → u/PrepperDisk]

Yea a spreadsheet that can be sorted and filtered by various metrics.

Also I feel like using the word “only” implies an opinion that the amount they lasted is not enough. But maybe that’s just me.

[u/totheendandbackagain → u/ExpletiveDeIeted]

Super impressive work

I would consider only mentioning cards that have failed, as they give the total lifetime. The alternative is saying "one card has only done 1 write cycle, because it was bought yesterday". This will reduce the volume of cards written up, but increase the data certainty.

As others have noted I like the ratio life:cost too, it's the decision factor most consumers would want to use

[u/mikaey00 → u/totheendandbackagain]

Yeah...the problem with that is that prices tend to be highly subjective. I feel like I got good deals on a lot of the cards I bought -- but I also bought a lot of my cards before the current flash shortage.

For example -- the single card that's gotten the best life:cost ratio? One of my Hiksemi NEO 8GB's. I managed to pick them up for $1.03 back in 2023. It has a life:cost ration of about 1.12TBW per dollar. But the other two samples didn't do quite so well -- they only got 153.98TBW per dollar and 45.90TBW per dollar.

So I guess if you're going to rate them that way...then which models have had the best life:cost ratio so far?

1. Hiksemi NEO 8GB (439.50TBW per dollar)
2. Lexar Blue 633x 32GB (374.35TBW per dollar)
3. Netac P500 Security Edition 64GB (314.47TBW per dollar)
4. HP MicroSDXC mx330 64GB (313.25TBW per dollar)
5. AUGAOKE 64GB (281.37TBW per dollar)

[u/mfitzp → u/mikaey00]

There are statistical tests you can do on this data to get some more objective results, accounting for the different numbers of different cards you have.

Ideally there should be stats for time, go written and number of writes vs chance of failure do each card.

Once you have that you can compare that directly vs the price to get a sense of what you’re paying for.

[u/guischmitd → u/mfitzp]

Came here to comment this, in college iirc we modeled failure due to mechanical fatigue with a weibull distribution, I imagine it's adequate for this use case as well. The intuition is you only get actual information about endurance once the thing fails, and the practical limitation is you need multiple samples of the same thing failing to get any kind of meaningful number

[u/mikaey00 → u/mfitzp]

Alright...you challenged me to be better. Thank you for that.

Since this sub doesn't allow images in the comments, see this thread instead.

[u/Zehryo → u/mikaey00]

You're a hero.

[u/EquipLordBritish → u/mikaey00]

This work is all the more important and useful now that there is a shortage so people can make informed decisions.

[u/lss2 → u/PrepperDisk]

How’s this visual?

https://claude.ai/public/artifacts/a7529bca-10cf-48f6-a48f-1168dea95ce8

[u/TurdBomb → u/lss2]

I usually hate AI anything, but this was super cool. Good use of AI to make simple visuals

[u/radiowave911 → u/TurdBomb]

Same. Not really a fan of using AI for most stuff, but I do have to admit it did a good job here.

[u/burnt-store-studio → u/lss2]

This is a great chart!

Question please? I’ve never used Claude, so I’ve no idea of the workflow. Did you simply point Claude at this Reddit post? Or did you do some massaging to get it as-is? I’m sorry for the ignorance; but thank you for any time you spend responding 🙂.

[u/lss2 → u/burnt-store-studio]

I said “Visualise this data” and copy pasted the post text, using Opus 5 High

[u/burnt-store-studio → u/lss2]

Thank you so much for taking the time to respond! And, again, for posting the infographic.

[u/xteron → u/lss2]

This is a good example where AI is a useful tool.

[u/BadPunCentral → u/PrepperDisk]

Yes if you’ve got different card sizes the total write data isn’t difficult to figure out from text and a spreadsheet re 1 (number of) whole write cycle may be better at a glance. But great work overall !

[u/ViciousBarnacle]

I once bought 30 SanDisk cards to give out to my photographers. It must have been a bad batch of plastic, because over the next couple months they just started kind of crumbling apart. My guys would just chuck em away and move onto the next one. Took a while to even know we had an issue.

SanDisk gave me such a run around. Even though I could prove the purchase they said they would replace only 1 of the cards. And only with a photo.

I swore that day that I would cost them more in sales than it would have cost them to replace my cards.

This is probably the greatest moment I have ever had to come through on that promise.

Please internet, make this count.

[u/UltraLisp → u/ViciousBarnacle]

Aight bro, I got you. SanDisk is out …and they literally were my favorite.

[u/ViciousBarnacle → u/UltraLisp]

Thank you my friend.

[u/wowsomuchempty → u/UltraLisp]

Yeah. I have been recommending them. This was on vibes, not data. They are out.

[u/ViciousBarnacle → u/wowsomuchempty]

Thank you!

[u/Collection_Same → u/UltraLisp]

Fuck sandisk ssds have literally fucked up on 100k jobs.

[u/BrokenByReddit → u/ViciousBarnacle]

So you're saying that SanDisk wouldn't refund the money you spent on SanDisk SD cards even though your SanDisk SD cards were obviously defective? 

[u/ViciousBarnacle → u/BrokenByReddit]

Yes. Exactly. And i have been slowly exacting my revenge on them for the last 7 years or so.

[u/chevyi6 → u/ViciousBarnacle]

I never want to buy another SanDisk now, and that's mostly what I buy. Unreal.

[u/kooknboo → u/BrokenByReddit]

They’re also saying they had no way to prove that the cards were defective because they were being tossed. This isn’t an obvious SanDisk rage opportunity.

[u/ViciousBarnacle → u/kooknboo]

It doesnt have to be rage necessarlily though. My position on SanDisk is the result of them making a crappy product and then not standing behind it. If my little photography company sold a bunch of people garbage that they couldn't use, we would go out of business real quick.

Apparently, as consumers, this is our only real recourse.

[u/Collection_Same → u/BrokenByReddit]

And who gives a fuck when the price of replacement is a fraction of the job. Just pass on the bad news to help others and never go back.

[u/uChoice_Reindeer7903 → u/ViciousBarnacle]

I’m the most computer illiterate person you’ll ever meet, I’ll try my best to not purchase anymore sandisk items (with that said I probably won’t purchase many SD cards anyway, but yeah). I can’t stand when big companies get so big they feel like they can just screw their customers over.

[u/ViciousBarnacle → u/uChoice_Reindeer7903]

For real. Its just gotten ridiculous these days. Regular people always just get stuck holding the bag.

Thank you for joining my crusade!

And remember! They also make hard drives!

[u/agendiau → u/ViciousBarnacle]

I love a good capitalist revenge story.

[u/DJ_Sk8Nite → u/ViciousBarnacle]

I’m with you. Fuck SanDisk. I’ve run a repair shop for 15yrs and the only brand SSDs I’ve had come back are SanDisk. They suck ass and didn’t warranty a single one for me all under a year.

[u/Collection_Same → u/DJ_Sk8Nite]

Legit. This. Yes.

[u/mcAlt009 → u/ViciousBarnacle]

I’ve already switched to pny because cost, but I’ll keep this in mind and avoid sandisk going forward.

They cost more than everyone else so it’s sorta weird they rank low 

[u/adobecredithours → u/ViciousBarnacle]

I was about to drop ten billy on SanDisk cards for my job as the official SD Card Kingpin for DARPA, but thanks to you I will be looking elsewhere.

More seriously though, I think all the cards I currently have (only like 3 in use tbh) are SanDisk...and now I'm concerned lol. Definitely won't be replacing those with more SanDisk cards after these test results and your call for vengeance.

[u/Nitrogen1234 → u/ViciousBarnacle]

I will never buy SanDisk again, pinky promise

[u/Srmon → u/ViciousBarnacle]

I usually buy SanDisk (for me it's once in a blue moon but I order periodically for work too) because at least they have a system to rank the speed of their cards and it's okay-ish to understand and the fast cards are indeed fast; but if a random internet stranger tells me they had a problem with this hyper capitalist brand and don't treat their customers right, they can suck it. Thanks for your input (and many many thanks to op too)

[u/BuboNovazealandiae → u/ViciousBarnacle]

And you have my bow.

Will tell our procurement team to never buy Sandisk again

[u/-venkman- → u/ViciousBarnacle]

I have been using sandisk cf and sd cards for 2 decades for photography and only one ever failed, so I may have been lucky or not written too much data on them?

[u/Snobolski → u/ViciousBarnacle]

Well, hot damn, now I have a new least-favorite SD card brand!

[u/kogun → u/ViciousBarnacle]

You convinced me, and that is the brand I've bought the most. No more.

[u/OrbitalCactus → u/ViciousBarnacle]

I was going to pick up a new card tomorrow. San-disk would have been my first choice. Not anymore! (Unless it’s literally all I can find, I only commit so much to a bit. And I really need it)

[u/Top_Schedule7264 → u/ViciousBarnacle]

I've unknowingly been on your side for years. I too had a junk SanDisk that crapped out in the first year. Haven't touched them since.

[u/Wonky_Willa]

Every once in a while you come across a post like this and it renews your belief in good Reddit content. Thanks for posting!

[u/smdarry]

That's some serious dedication to one cause.

[u/itrivers → u/smdarry]

This is Elite.

[u/xaeru]

TL;DR:

Skip the “high endurance” marketing tier, buy a good consumer card (PNY/Kingston Canvas) or go full industrial if the box actually matters.

[u/rocbolt → u/xaeru]

High Endurance is in theory for a very specific use case- security cams, dash cams, etc. I’ve had great luck (apparently) as I have all sandisk high endurance cards. Youngest is nearly 3 years old, oldest is approaching 8 years old of continuous 24 hour use in security cams. I’ve got 30 cameras, and I’ve had just one card go bad in that time. I thought I was losing a second a few years ago but turns out it was the card reader in the camera. Some of these cameras stare directly at the sun most of the day too in southern Arizona, it’s almost a game now to see how long they can go

[u/flymcb]

Forget all the endurance testing. The factory must grow.

[u/Brujamuja → u/flymcb]

The factory must grow

[u/calebtheredwood → u/Brujamuja]

I just broke 1,800 hrs. I'm tired boss.

[u/phenger → u/calebtheredwood]

Those are rookie numbers! You gotta pump those up!

[u/flymcb → u/calebtheredwood]

2664 (and counting) over here

[u/xxxlttxxx → u/flymcb]

5k and just started a nullius run

[u/knivengaffelnskeden → u/flymcb]

This is EXACTLY what I would think a Factorio player would be up to in his spare time, waiting for the next train with level 3 speed modules to finish! 😅 

[u/Darqfallen → u/flymcb]

I came to say the same!

[u/hanced01 → u/Darqfallen]

+1

[u/spinwizard69]

Nice work.

From what I can see the modern microSD card is pretty reliable. A Kingston industrial card looks to be a great place to stuff backups or to store a mirror of your git repository.

[u/isoAntti → u/spinwizard69]

It's with the arrival of dash cams which took everyone by surprise. Writing video Hours at an end to card which was previously used for photos filling up once twice year.

[u/Luckyth13teen]

Data put visually for my own consumption, figured others might like it

Consumer grade breakdown:

Brand	Avg. Days	P/V/E Cycles	Total Data Written	Key Takeaway
Amazon Basics	788 days	16,600	4.2 PB	Top Overall Performer: Impressive longevity for a budget option.
Kingston	694 days	23,500	11.6 PB	Excellent overall performance, especially the Select Plus line.
Lexar	684 days	15,800	5.8 PB	Solid, reliable performance; Longsys models seem robust.
Delkin Devices	662 days	13,500	5.1 PB	Highest Data Written per Card: A standout for sheer data endurance.
PNY	643 days	15,700	11.5 PB	The PRO Elite Prime line shows top-tier speed and endurance.
Samsung	553 days	11,100	7.2 PB	Consistently reliable, with a high total data written.

Durability comparison High endurance/Industrial

Brand	Avg. Days	P/V/E Cycles	Data Written	Key Note
Samsung	822 days	18,800	1.8 PB	Highest average days.
Transcend	760 days	17,000	3.2 PB	Consistent performance.
TEAMGROUP	404 days	17,300	2.2 PB	Potential, but early issues noted.
SanDisk	452 days	16,200	4.7 PB	Failed after high write volumes.
Kingston	779 days	141,600	3.4 PB	Highest cycles by far

Worst consumer

Brand	Avg. Days	P/V/E Cycles	Data Written	Summary
SanDisk (Consumer)	384 days	9,404	566 TBW	The biggest brand, but poor performance relative to others.
Silicon Power (SP)	159 days	2,350	252 TBW	Very low cycle count.
ADATA	236 days	2,350	74 TBW	Poor longevity.
Micro Center	116 days	3,421	214 TBW	Among the lowest performers.
Gigastone	114 days	4,845	133 TBW	Significantly underperformed.
onn	40 days	1,400	40 TBW	Worst endurance noted.

[u/otakugrey → u/Luckyth13teen]

Man, what the hell happened to Sandisk? They have always seemed like the best for about a decade.

[u/supersmashsiblings]

You should cross post this to r/sbcgaming, they would love this level of info since microsd card use is so integral to the hobby. 

[u/mikaey00 → u/supersmashsiblings]

Already did.

[u/QING-CHARLES → u/mikaey00]

And to r/DataHoarder if you didn't already.

[u/mikaey00 → u/QING-CHARLES]

Yup, already posted it there.

[u/abolish_karma → u/mikaey00]

Where's the donate button?

[u/pfak]

Lol not surprised re: adata. Thank you for doing this! 

[u/martin_xs6]

This is great! Would love a best bang for the buck summary!

Wondering if you've done any testing on poweroffs during writing? I used to teach a robotics class where we had ~20 raspberry pi based robots and would see a half dozen failures each year. The cards themselves (not the file systems) would get corrupted after unexpected power cycling. In our experience, the Samsung EVO and SanDisk extreme cards were least susceptible to this, but I'd be curious to know what your experience has been.

[u/mikaey00 → u/martin_xs6]

I haven't done this as its own test, but I have had some experience with it -- and almost all of it with SanDisk cards.

I've had instances where I plugged in a new card reader into a nearby USB port, and two SanDisk cards instantly stopped working. I've had instances where the power went out at my house, and when it came back on, one of my SanDisk cards stopped working. I've had instances where I had to pull a SanDisk card from its reader, and when I reinserted it, it stopped working. It's always the SanDisk cards that have this issue -- I think I've had maybe one non-SanDisk card that had this same issue.

[u/martin_xs6 → u/mikaey00]

Do you know which type of SanDisk card had the issues for you? For us it was the cheaper (non-extreme) ones that most frequently had issues.

Of course, whatever we bought, we also had to be really careful not to get scammed. Got a bunch of counterfeit ones until we learned where we could order from.

[u/mikaey00 → u/martin_xs6]

All of them. I've tested:

• SanDisk Extreme (32GB and 64GB)
• SanDisk Extreme PRO (32GB and 64GB)
• SanDisk High Endurance 64GB
• SanDisk ImageMate PRO 128GB
• SanDisk Industrial 8GB
• SanDisk MAX ENDURANCE 32GB
• SanDisk for Nintendo Switch 64GB
• SanDisk Outdoors FHD 32GB
• SanDisk Ultra (32GB and 128GB)
• WD Purple 32GB

I have come across some fake SanDisk cards. They're not represented here.

I have 38 SanDisk cards in total (including the consumer-grade, high endurance, and industrial grade). 32 are dead. They only lasted an average of about 10,000 program/verify/erase cycles before failing.

Now...which of those are the worst for endurance? The Ultra's. They only averaged about 3,300 program/verify/erase cycles before failing.

[u/cr4zybilly → u/martin_xs6]

This is my (entirely anecdotal) experience as well: power shutoffs kill cards, but everything is fine if you just let em run.

[u/SharkAttackOmNom]

Has there been more or less failures as a function of proximity to the cactus.

But actually, have you trended data of performance related to individual pi’s or card readers or usb hubs. I wonder if any of the hardware used could cause anomalous results.

[u/IronEngineer]

If you're interested I could help you calculate a mean time before failure for each brand of microsd from this test data.  I've done this before in reliability testing for my job.  Let me know if you are interested.

[u/TheTxoof → u/IronEngineer]

I just completed a stats course and my stats-antennas are quivering. Maybe with your background you can help me understand?

The sample size is low per brand and capacity. There's no long term data across a single type/make of card.

Maybe there's enough data for an ANOVA test between name brand and off brand and generic. But I don't think there's enough statistical power within each brand/size to make any claims.

[u/IronEngineer → u/TheTxoof]

For mean time before failure calculations I typically use a chi-2 test.  Most commonly you run a number of systems (say 6 or so) to failure or to a number of cycles.  ie if you want to demonstrate a ten year mtbf you would run an accelerated test for 15 years (accelerated).  You now have a record of systems making it to different amount of lifetimes or even making it the whole 15 years.  You then can make a calculation with either 60% or 90% certainty (your choice of what confidence level you want) on what the mtbf is.  ie you could calculate that with 90% certainty mtbf is at least 12 years.  

There is a really good 4 page descriptor sheet from the army reliability group explaining the algorithm step by step.  I'll try to find it.

For people interested in reliability, also look up the bathtub curve.   Here is a very simplified idea.  Parts fail for two large reasons.  Manufacturing defects and wearing out.  You tend to have a lot of failures up front, then a constant rate (hopefully low) of failures due to things wearing out) then a large spike in failures above the mtbf as it completely wears out.  Most manufacturers try to induce a small amount of wear in their devices to shake out the manufacturing defects before they ship to a customer.  

It's a fun and very statistically driven field.

[u/Northern23]

Where did you buy the cards from? If Amazon, how did you make sure they're authentic cards and not counterfeits?

[u/UltraLisp → u/Northern23]

The real questions

[u/m__a__s]

I wonder how many are counterfeit. Especially Samsung---not that their genuine ones were very reliable.

[u/cr4zybilly → u/m__a__s]

SanDisk too - the number of fake garbage cards on ebay, Amazon, even Marketplace, is bonkers.

[u/m__a__s → u/cr4zybilly]

Indeed! How did I forget to mention SanDisk?

[u/canton7]

THANK YOU! I make medical devices, and I came across your website when trying get to the bottom of SD card failures we've been seeing in the field. The data you've gathered was really useful in trying to explain the failure rates we'd been seeing, and suggest alternative ways forward.

[u/kayjay707]

The level of dedication that went into this is insane. I read this entirely because I narrowed down SanDisk Max Endurance for my dash cam.

My current micro SD gives an error that says “Slow Card”.
Which one would you recommend for a Dashcam? 256GB

[u/saturnine23 → u/kayjay707]

Seconding this, 👋🏻 I'm also dashcam user that essentially subjects my MicroSD card to an endless torture loop of writing and rewriting video LOL

[u/thrillsbury]

/r/buyitforlife /r/photography

[u/dark-trojan]

Just wanted to let you know that Amazon basics is basically lexar sd cards rebranded

[u/BuboNovazealandiae]

I want to upvote twice for the bonus doggo playing Factorio

[u/Dragontech97]

This guy NANDs, well done

[u/RisusSardonicus4622]

The factory must grow

[u/realfathonix]

So sad that SanDisk doesn't make great consumer cards anymore. I don't know exactly how many TBs have burned but all of my SanDisk Extreme Ultra cards from 2013-2015 are still going strong to this day, living across different phones and SBCs surviving countless reformats.

OTOH my Lexar Blue from 3 years ago has suffered from data corruption despite I've only used it on SBCs three times and most of its life was on my phone. I don't record very often either. Doesn't seem to align with OP findings or I got a bad batch, idk.

Edit: Wrong model. Also I don't mean SanDisk and Lexar are the same thing.

[u/gsmitheidw1]

Two questions:

1. Are some devices just other ones rebranded? My guess is there probably aren't that many SD card manufacturers and some are just others rebranded

2. What defines high endurance? The label or the internals.. I would guess high endurance implies single layer cells rather than double or tripplen etc. But it would be interesting to note it single layer was an advantage. Maybe it's simply a matter of cheap triple layer but extra spare cells unused until needed. I'd love to know how the better ones are better.

[u/mikaey00 → u/gsmitheidw1]

Hi!

1. To some extent, yes. For example, HP's microSD cards were made by PNY (a fact which they didn't try to hide very well).
2. For my purposes, it's any non-industrial grade cards that either (a) are labelled as "high endurance", or (b) make a stated endurance claim.

[u/grahamw01]

Amazing stuff. I'd be cautious about rebrands (such as Amazon Basics) because they can and will switch to a cheaper manufacturer at any time.

[u/Rate-Other]

Of course you play factorio

[u/CHILLAS317]

Mmhmm. Be honest. You did? Or the dog did?

[u/mikaey00 → u/CHILLAS317]

She helped.

[u/kaptnblackbeard]

The only time I've had flash media (including SD Cards, USB, etc) fail is when they haven't been used in some time. That I think is where the majority of testing falls short, it rarely if ever tests unused time to failure.

I understand this would greatly increase the testing costs since testing the read/write of an unused card instantly makes it used.

[u/vodkabuzz]

You say you’ve “written about #PB to them.” Is that per card? Or across all cards in the brand+group?

[u/mikaey00 → u/vodkabuzz]

In the "who makes the best cards?" section, that's the sum total across all cards in that brand/group. In the "who makes the worst cards?" section, I switched to the average per card.

In hindsight, I could have written that better.

[u/vodkabuzz → u/mikaey00]

Good deal. Great stress tests you’re doing!

[u/Mero80]

How does Patriot memory look amongst these if you’ve tested them at all?

[u/MyStoopidStuff]

Thank you for doing this! It gives me some confirmation of what I suspected regarding Sandisk and Samsung cards, but also PNY. I keep a small box for failed cards over the years, to remind me which brands to avoid. There are several Sandisk in there, a couple Samsung, and no PNY cards. It's also interesting to see how well TeamGroup did for the high endurance cards. I've sort'a avoided them, but even with the issues you saw, I'll probably get one the next time I see them on sale.

[u/MaapuSeeSore]

This needs to be posted in sdcard , dashcam ,hardware subs

Post like this is what it means to find gems in a pile of infinite garbage on the internet

[u/B_Huij]

Fascinating results. I’d love to see some visualizations or tabular data to summarize main takeaways.

[u/g-o-u-l-a]

I have no need for this information, yet, I’m glad I read it. Very cool, very interesting. Thanks for sharing!

[u/Zehryo]

You've found a dog?!
Quick, give it plenty of scratchies and cuddles!!!!!!

[u/dox81]

Congrats, man! Really good stuff

[u/rhif-wervl]

And making sure the factory keeps growing at the same time, good work multitasking!

[u/McDonaldsWitchcraft]

that's cool! Have you released this as a dataset somewhere? That would be very useful

[u/thejadephoenix]

Very interesting stuff. 

I'm curious though, because a lot of sellers on looking Amazon or eBay aren't necessarily selling legitimate versions are they verified to be authentic? 

And do you track/include where each card came from if/when it fails to see if there's any kind of common thing like cards from Amazon fail at higher rates than Walmart or etc...

Those minor things aside, keep up the good work. 

[u/Open_Square670]

Thanks for doing this bro. Incredible dedication

[u/tcneo16]

thank you for your service

[u/jbar3640]

my personal experience with SD cards is so frustrating. Kingston and SanDisk were "good" cards in my mind, but I can confirm they aren't.

I like your work, that's awesome!

[u/Mr_Lumbergh]

What’s the doggo’s name?

[u/kenkitt]

There are also Chinese clones mostly sold for resale at very cheap cost a pack of say 10 64gbs would cost like 20$ also test them they are on AliExpress. Nice work

[u/xander255]

Upvote for the Lower Decks reference.

[u/Fit-Decision-7617]

Show us the factory. Is it growing?

[u/nyzaa]

Thats a lot of time you dedicate yourself into. Nice work, we all appreciate this independent research you've done.

As for performance and durability, i agree on your result of PNY. Almost all (maybe 80+%) of my mobile storage were made by them. USB flash drives, sd, micro sd, and ssd army of mine were PNY. Theyre all affordable, durable, and fast considering the price they've given.

For microSD category, unfortunately its rare who sells them in my area, i only have 1 PNY microsd, the rest of mine were by Sandisk. The SSD though, were cheap and durable, i have 8 of them. Im still using an old ssd of theirs made in 2014 (120gb) running on win7 for my offline workstation and no trouble at all since the first time i installed it. The other 4 of my PNY SSDs (newer model -above 2020) were used for the c:/ drives for my other computers and i made 3 of them to become a portable ssd using additional enclosure. Never broke down, no drama, no tantrum, stable speed.

Anyway nice info and stats you gather. Good work and keep it up 👍

.

*) Disclaimer, im no whatsoever related to the PNY company or their affiliates, the reason i bought them back then was because (iirc) they're on introduction sale price and the booth shows the manufacturing process video of it. Im impressed, doubt it but still winging it, bought it, use it, then in love with it. That's all.

[u/tomstorey_]

+1000000 for doggo pic

[u/C_M_O_TDibbler]

Checks laptop screen.... yep this is 100% Factorio player base behaviour

[u/adrenozin]

For some reason I imagined you played factorio...

[u/External-Earth-4845]

Incredible dataset, very cool. Did you track ambient temperature in the testing space? Even spot check once a week?

[u/AmiDeplorabilis]

Whatever your day job is, if this isn't it, it should be... I've not EVER seen such thorough testing from a single individual.

And I'm reading the whole thing... no TLDR here.

[u/huskyghost]

My factorio brother! The factory must grow.

[u/Robobvious]

Neat! Now I wonder if those cheap microcenter usb’s they have at checkout fail faster than others.

[u/mondain]

And as expected I just got a 5 pack of 8Gb Gigastone; I wish I'd seen your update beforehand; you sir are a prince for this work and level of detail, thank you. Back to the cards, I think they'll be fine for me since I only use them to store OS ISO images for installs, luckily.

[u/FreakPC]

TL;DR:

According to the photos you found a dog. Case closed.

[u/Ciggimon]

Great Work, also cute dog

[u/krizd]

Plug ya patreon all you like… there’s some serious dedication to this work that takes love for the game… good job.

[u/depressed_crustacean]

Didn't read. dog + factorio nuff said

[u/drankinatty]

Dog tax looks like a familiar Belgium I know. That's who I took to be the supervisor.

On a serious note, you have done some fantastic work and providing the results speaks to the best of what we can all contribute to the community/society/et. al. Well done.

[u/TheNightLard]

That a huge dedication and effort. Thanks for doing it

[u/MUnt_0]

Dementrous work, OP. Very interresring !

Am I really surprised you're a Factorio player ? No.

[u/Grabbels]

You’re basically playing factorio IRL

[u/OldDirtyGurt]

Have you been diagnosed?

[u/mickynuts]

Whoa, really impressive and helpful. Thank you for sharing which was a pleasure to read. Good luck for the rest of the tests.

[u/D-Alembert]

Mikaey00 the MVP

Thank you!

[u/JustReguIar]

So my question would be all in all which one would you deem the “best” bang for your buck?

[u/snapetom]

Wow, thanks for this.

Surprised about Teamgroup, too. I bought 5 256GB high endurance cards for a Pi cluster about 2 years ago. The cluster runs 24/7 with light Kubernetes work. About three months ago, two of them failed in the same week. I was so pissed, I switched to Samsungs.

[u/jnsy617]

This makes me happy that I mostly have a bunch of PNY, Kingston, and Lexar consumer-grade cards.

In your opinion, does the size of the card (how much it holds) matter as to how much it fails or is more the brand that matters?

I would be curious how your experience compares to regular-sized SD cards as well.

[u/Plenty_Airline_5803]

This is great, thank you for the research.

[u/cdf_sir]

If im going to do a test, id probably do it on a device that can talk to the sd card directly. So far any rooted android devices with sd card slot and hacked Nintendo switch i know can do this.

Card readers on the ither hand..specifically USB. I dont know....

[u/onray88]

Thank you for confirming my suspicions about onn, I used one for a indoor security cam and the card died after about 3 months

[u/jameside]

Posting so I can be a part of this legendary thread.

[u/SureUnderstanding358]

Interesting. I have about 100 sandisk industrial cards deployed going on 3+ years now and now a not a single failure. That being said, they don’t nearly see the profile you’re using for your test…but under my normal operating conditions they’re darn reliable.

[u/gzushd]

Thank you for this. This is amazing. Incredible test set up and data collection. Hope pny and Kingston start sending you some free cards because that’s all I’m gonna be buying for a while.

[u/squall333]

Is there a correlation between write speed and failure speed?

[u/xylarr]

Have an upvote for your hard working employee

[u/Mingyao_13]

bro thx for testing. not a good time to do any longevity stress test with the cost of everything

[u/Extreme_Turnover_838]

Have you done bit-rot testing? This means how long the cards can hold their contents without being used. A few of mine seem to have lost their contents somewhere around 1 year of inactivity.

[u/keeldude]

Thats awesome. You've inspired me to try running an RPI flat out doing video encoding and journal logging 24/7 to test random SD cards. Another real test would be to power cycle it mid write, etc.

[u/Beerseidon]

Truly amazing effort here. Well done. This is a post I will come back to, thank you OP

[u/G_Laoshi]

He Is a Man of Focus, Commitment and Sheer Fucking Will

[u/Xenothinker]

Nice work Matt, and a lovely dog.

[u/ShakataGaNai]

Love this. Amazing stuff. It's a sample size of 1, so means nothing. But I bought a Sandisk 128GB high endurance card in 2023 for my Raspberry Pi ADSB unit. Installed dietpi which has special low-write mode. Still died within about a year, maybe 18mo.

[u/Ski_Sunday]

And here was me thinking that my Sandisk cards must be fake ones as they keep failing, little did i realise they are just shite

[u/weltvonalex]

That is incredible, thank you.

[u/kahnstyle]

This is very impressive, but would you be receptive to someone suggesting some cable management solutions lol

[u/-a-p-b-]

I just wanna pet the dog. 🐶

[u/toyfreddym8]

Did your helper keep you entertained?

[u/lam3001]

So… I should get an SSD for my Pi real soon

[u/__g_e_o_r_g_e__]

Your dedication is a huge asset to the community. Glad my suspicions about Sandisk were confirmed - a case study in marketing vs. product quality.

If you ever reach the end of this test, may I suggest you try a new test - fill the cards to 90% then repeatedly rewrite the same 4k file, using a traditional filesystem that's not flash optimized (doesn't spead the writes). This is a worst case scenario but more common in operating systems - especially via misconfiguration. Maybe start with cheap cards as this will kill them quick! Maybe one will shine though...

[u/N0xF0rt]

Who made the best cards?

[u/___Syntax-Error___]

You didn't test angelbird Micro SD?

[u/AleksElixirr]

Wow u found a dog, could you give the steps to summon the beast?

[u/dolphindidler]

So do I get this right: even though sandisk is not good compared to the others, the cards lasted 9,4k rewrite cycles? I would assume now, that they are not great for a raspberry pi but if I use it for my camera, it would be a good choice still, because 9k cycles of deleting and writing is most likely more than I will ever need in my photography lifetime.
Not sure if my thinking is right though

[u/Formal_Classroom_430]

As a product owner of 2 SP Silicon Power Silicon Power 32GB cards, I am disappointed. Bought them for 4 dollars each at start of month mostly because my old devices are limited to 32GB and not able to grad good ones.

[u/g6b0rr]

U are a Hero! Thanks for sharing!

[u/Kurgan_IT]

Really interesting idea, but... since every manufacturer nowadays swaps the internal parts of their products for the cheapest they can find all the time, and do this without even changing the model name or even the SKU (sometimes)... does this make sense at all?

I mean, it's a great insight into the past of every maker and model. It might say something about the present or the future, or maybe nothing at all.

PS: I'd consider a card failed as soon as it reports an error, not 50% of bad sectors.

[u/billyshin]

All that work and not one mention of Toshiba (Kioxia) cards.

[u/isoAntti]

This sounds to me the more certain model is used the more reliable it is. Industrial and high endurance being some niches so failing easy.

My exp, about 50 rpis with SanDisk extreme/e pro with minimal writes all working. Failed are pny and nonames.

[u/x_Carlos_Danger_x]

Lmao, of course you're a fellow Factorio player 😂 Interesting project!

[u/glennkg]

I see a cactus in the picture but no cactus brand industrial microsd!

Ok selfish guilting aside, great work on this. Thank you for tearing

[u/tcneo16]

i just want to confirm that i’m reading this right as i’m going to buy some cards soon for casual use.

so for consumer grade, the 5 brands that are good are PNY, Kingston, Delkin, Lexar and Samsung?

[u/mikaey00 → u/tcneo16]

Yep!

[u/atomicsilence]

Doing the Lords work, thank you brother nerd.

[u/Chris_palatina]

The factory must grow!

[u/Collection_Same]

Sandisk ceo should basically eat shit to compensate their issues. Money doesn’t cut it.

[u/Richardrsb]

No Angelbird cards tested?

[u/SJsharkie925]

Only a small handful of these companies actually make NAND. Samsung, SanDisk, Micron, Kioxia, SK Hynnex. All the others on your list buy on the market. The bin that is used determines the grade and as a result the endurance.

[u/sweetpete74]

Thanks for sharing this and all your hard work. I’ve bookmarked it to come back to and will check out your Patreon and blog.

One ask, and maybe you already address it in your blog, would be to share the read/write amount per brand as multiple of the amount of storage for that brand or card. So if you have (made up numbers) 50 TB of storage in a brand with mixed capacities, and you’ve done 10 PB of IO so far, it’s 200x IO to storage. I’d love to see that per brand per category and per card size in each brand/category.

[u/gotBurner]

I may have missed it. What’s the game on the laptop that good dog is playing?

[u/mikaey00 → u/gotBurner]

Factorio.

[u/Vortex_Radar]

Amazing work! Thank you! I've had one or two SanDisks fail over the years, but it's great seeing your reports with much more extensive testing. I'll definitely be sharing your test results with people. :)

[u/snail-gorski]

Totally agree on SanDisk those are disposable sd cards. You better get a new one every time you take them out. 

[u/Vortex_Radar]

I noticed both of the industrial rated cards are only 8GB, while many of the Endurance rated cards are 32-64GB, and that should change things. All things being equal, wouldn't a larger card be better given that it can store more data in total and require fewer rewrite cycles? 10,000 rewrites on a 64 GB card allows you to store way more data than 10,000 rewrites on an 8 GB card.

I'm thinking about applications like dash camera recording where you're constantly looping over old footage, and in that situation a larger capacity card should let you record longer with fewer rewrites and last longer.

Given that you're testing with different sized cards, perhaps the metrics should also consider total data pushed and not just rewrites alone.