Do Camera Memory Cards Wear Out?

Digital memory cards are tough little things, but it's still possible to wear them out. At least in theory. But it's not a practical concern for the vast majority of photographers.

Digital memory cards are tough little things. They can put up with a lot more than most cameras. They can breeze through airport security x-rays without a hitch, don’t mind being dropped, are immune to magnets, can often emerge unscathed by an accidental run through a washing machine, and, if you’re really lucky, can even last for a good stint submerged in sea water.. SanDisk is even going to so far as to officially claim on the packaging of its new Extreme SDHC cards that they are waterproof, temperature proof, shock proof, x-ray proof, and magnet proof.

While all current model memory cards boast flash memory, the physical design of Secure Digital (SD) and microSD cards make them a bit more resilient than most Compact Flash (CF) cards: they’re smaller, lighter, and able to handle dust and sand better than Compact Flash (CF) cards (CF cards have 50 small holes on one face that the pins in your camera or card reader go in, which offer perfect hiding places for dust and sand). The standard models are resilient on their own, but you can also get extra tough models that are built for the rigors of more writing cycles (such as for use in security cameras or dashcams).

But all flash memory cards can wear out, at least in theory. In practice, it takes an awful lot of use and isn’t a practical concern for the vast majority of photographers. A figure of 100,000 write cycles used to be bandied about as a standard measure of what’s known as Mean Time Before Failure (MTBF), but more modern cards measure their failure rates in millions of hours of continuous use. Card manufacturers build into the card controller features that help with distributing the write cycles evenly across the card so that no one spot gets much more use than any other, a process known as wear leveling. But the very fact that wear leveling is built in is a good indicator that there is some wear.

In practice, wearing out a memory card isn’t a practical concern in most cases. A card manufactured in the past couple of years is likely to take normal usage conditions in its stride. And for abnormally demanding uses, industrial grade cards are available that are manufactured to higher standards. That said, working pros will typically replace their cards fairly regularly. The relatively modest cost of most standard-sized memory cards is a small price to minimize the risk of losing images for a client.

Unfortunately, though, as low as the risk of wearing out a card is, if the card’s going to go it will probably go suddenly without warning. So it’s a good idea to build sensible precautions into your workflow to minimize the risks of losing large numbers of images if something does happen to go wrong somewhere along the line. That means having backup cards on hand, downloading your images regularly, and formatting the cards in camera after downloading the images. There’s no hard-and-fast rule on how often you should replace your memory cards; it’s something to start thinking about when you’re getting up into the millions of images on a card (or hundreds of thousands if your card is an older model). Of course, if you’ve shot that many images, chances are you also have to start worrying about failure of the shutter mechanism in your DSLR. But that’s another story . . .

If you’re technically inclined, here’s a 2003 SanDisk paper on wear leveling in flash memory cards.

And KEH has put together a great primer on memory cards, including common error codes.

Tips for Using and Caring for Your Memory Cards

Like just about any product, especially an electronic one, it is possible for a brand new memory card to be faulty. So always check that it’s working normally before you head off on that once-in-a-lifetime trip. And always take at least one or two spare cards with you.

Always format the card in camera rather than on your computer. While the latter might well work, camera and card manufacturers usually recommend doing it in camera to avoid data errors. It’s the safer option.

Always download the images to your computer as soon as practicable and edit and archive from there. Trying to edit images directly on the memory card can lead to problems, and flash memory cards are not designed for long-term archival storage. Treat them as a temporary step between your camera and your fully backed-up image archive.

Take a spare. Or two.

Replace the cards on a schedule that makes sense for the type of shooting you’re doing. If you only take occasional snapshots, every couple of years might be fine. If you’re working pro taking hundreds or thousands of shots day in day out, much more often is a better idea.

Protect your memory cards while in the field. Here are some ideas.

View Comments

  • I have had my SD card in my Canon A430 Powershot camera for about 10 years and maybe taken only 5000 excellent images. At a funeral recently I took a dozen pictures and they all turned out as blue smudges, a complete disaster. It was a 40c day (107F). This is the only reason I can think of that caused the failure. Since then all new images are at a very low resolution or have a yellow wash effect. I will try a new card to see what happens.

  • There are surprisingly few articles on this topic online. Thanks for the summary.

    I might add the durability is going to vary by manufacturer. I would stick to name brands and read reviews to get a feel for which cards tend to hold up better. Common sense would say that the harder you use them, the sooner they are likely to fail. Also, consider how willing you are to lose the photos that are on the card.

    Personally, as a former computer consultant and now a photographer doing work for clients, I never rely on any one media to store anything. My workflow is to download my photos from the SD card to my computer as soon as I get back from the shoot into a folder in my Google Drive, which will then sync automatically to the cloud. Before I do a new shoot, I reformat the card in the camera that will be doing the shooting.

    Also, I would think that video is going to be harder on SD cards than still photos because it's a constant write to the card and the camera is going to get hotter. Heat is the enemy of electronics of any kind. Also, the files are much larger, so the potential of a corrupted file goes up. If you do a lot of video, I would consider replacing more frequently.

    It's been about 18 months since we bought our last cards for our business and I may start replacing them soon, just to be extra cautious. Spending a couple hundred bucks every year or two to prevent footage that can never be retaken from being lost is a no-brainer to me.

  • Importing images from a Lexar Multi slot reader into Final Cut ProX is, after years of no problems whatsoever, now importing in duplicates.
    It's not recording duplicate in my Canon XF300....so something is happening either with the cards (it's happened on 3 different cards) or the Reader. Lexar say it's not their problem. The problem seems to have started when Mac moved to Sierra. Any advice would be gratefully received

    • I've not run into that issue before, but it doesn't sound to me like a fault with the cards, especially since you've tried three of them. There have also been two updates to Final Cut Pro in the last 6 weeks--a big one in late October and a smaller bugfix since then--and I wonder if it had something to do with that. It would be worth trying to import from the cards using Mac OSX's built-in Image Capture app to see if it does the same thing.

  • Wearing out is one issue. The controllers have to deal with more errors and slower performance as they get older. It may not be a card per se, but one of my SanDisk USB flash drives is getting slower and slower. It's still reliable, but sometimes it takes a half minute just to open a directory.

    The other issue is that some people buy memory cards and think that they'll be OK for archival purposes. Even no bit location is written to more than once, there is the issue of charge leakage. Some memory card/drive controllers will eventually move around data to fight charge leakage before it leaks enough such that it's unreadable. Since it's written to another area, the charge is refreshed.

  • The pictures taken with my digital camera are not a clear [crisp] anymore as they once where
    what could be the reason for that? I've had the camera since 2007 and have taken about 35 CD's full of pictures. Could the memory card be getting weak?

    • No, it's very unlikely to be anything to do with the memory card. It could be something smeared on the lens, perhaps the image sense has been knocked out of place, the AF system isn't working properly, or a host of other mechanical issues.

      • Unless there is actual corruption in the picture (like missing pixels or entire sections of the image missing), it's going to be a physical problem with the camera, like a dirty lens or dust in the sensor. Digital is an either/or thing - 1's or 0's. It's either there or it's not.

Share