Fake SD cards are increasingly common, and often store way fewer files than their legit counterparts, and can put your data at risk. But how can you tell a fake SD card from a real one?

If you’re paying an unusually low price for an SD card compared to everywhere else, the chances are, you’re buying a fake. While it can be tempting to find a high capacity SD card at the lowest possible price, in the long run, it’s going to cost you more. As well as being a bad investment, fake SD cards are risky to use in your devices, and can result in data loss. It can often be very difficult to spot a fake SD card from a genuine one, as scammers go to great lengths to make them look like the real thing. Some fake SD cards are so realistic, it can be difficult to tell them from the real thing without a closer look. The top culprits for selling fake SD cards are Wish, eBay and Amazon Marketplace, although it isn’t unheard of for fake SD cards to make it into the supply of more trusted outlets. No brand is particularly safe, so there’s a chance your SanDisk, Samsung or Kingston SD cards might not be genuine.

Fake SD cards can make their way into the legit marketplace through refunds. After purchasing a genuine product from a reputable seller, scammers then ask for a refund, and unbeknownst to the person dealing with the request, handing back a fake SD card, while keeping the legit one for themselves. The fake SD card they hand back could be near-identical to the original, but produced at a fraction of the cost. This fake SD could then be sold unwittingly to another customer, who might only find out at the worst possible time when their data is at risk.

It can be very difficult – if not impossible – to tell a genuine SD card from a fake. Fake SD cards can often be identified not by the card itself, but by the packaging; poorly disguised packaging and incorrect serial numbers can give the game away. Reduced read/write speeds can be another giveaway. An SD might have an advertised speed of 100 MB/second, but when tested, might have half the speed. Another massive giveaway is storage capacity. This can be harder to spot than reduced speeds, because the part of the SD card responsible for displaying the storage may have been programmed to show a false reading; you might have an SD card with a purported storage capacity of 128 GB, but it might only store 50 GB. These fakes can be more convincing, and will only become apparent when you reach the actual storage limit and can’t write any more files to the device.

To protect yourself against fake SD cards, only buy from reputed sellers. Smaller sellers are generally at less risk from fake SD cards than larger ones, who might sell hundreds of SD cards every day, and are more likely to let fakes get into their supply. You should also test your SD card as soon as you purchase it. Using software such as CrystalDiskMark, you can test the read/write speeds. If you want to test the storage capacity, H2Test2w can be used.