Free Tools to Check SD Card Speed and Capacity

SD and microSD cards are used for storage in a variety of devices. For example, you may move your offline Spotify playlist to an microSD card. Unfortunately, there are many fake SD and microSD cards floating around on the Internet. Even reputable online marketplaces like Amazon aren’t immune to the influx of useless cards being flogged to unsuspecting consumers. That’s why you need a fake SD card test to avoid getting scammed.

Common Types of Fake SD Cards

Sometimes these fake cards are from no-name brands; other times they’re counterfeits of recognizable and trusted brands. For instance, you might find a great deal on a SanDisk SD card, but in reality, it’s just a scam.

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Either way, they scam buyers in one of two ways: by offering a brand name at an unbelievable discount or by offering a generic brand with a crazy amount of storage for nearly nothing. While the offers are tempting, these cards often only last for a few weeks or months before they stop working completely.

The most common scam is falsely stating the card’s capacity. For example, a card is advertised as 256GB; however, it really only holds 4GB. In some cases the card corrupts data, rendering it useless. Fortunately, there are a number of free tools that can test the speed and capacity of your cards. Before you order a large batch of super cheap SD cards, buy one and test it to make sure you’re getting what you pay for.

1. H2testw

H2testw has been around for a very long time and for good reason. This reliable tool is able to test the true capacity of an SD/microSD card, as well as the read/write speed of the drive. The only downside to H2testw is the fact that it is quite old. This means that the software has not been optimized to be used on larger-capacity drives. While H2testw will work on any size drive, it may take a bit longer to complete the test.

H2testw was originally developed by a German software engineer. As such, the website that hosts the fake SD card test software, as well as the software itself, is in German. However, don’t let that scare you. Downloading the installer from the website is self-explanatory, regardless of your German language skills. Once downloaded, simply run the installer. After the first run it will give users the option to use English as the default language. H2testw is only available on Windows; however, it can be run on Linux and Mac via a virtual machine.

2. FakeFlashTest

If you’re looking for something a bit speedier than H2testw, consider FakeFlashTest. This tool is very similar to H2testw in that it writes data to your SD card in order to determine read/write speed and capacity. However, FakeFlashTest speeds up the fake SD card test by offering a “Quick Size Test.” This function writes and reads 512 bytes of data at random sectors across the card. This enables much faster test results, which is particularly ideal for larger capacity cards.

It should be noted that the “Quick Size Test” is destructive, meaning that any data on the card will be wiped. There is an option to test a card without resulting in data loss; however, it takes much more time to complete. We strongly suggest that you back up any data, regardless of which test you opt for.

3. ChipGenius

Whereas both FakeFlashTest and H2testw write data to the SD card in order to determine capacity, ChipGenius doesn’t write any data at all. Instead, ChipGenius locates the vendor (manufacturer) information as well as storage information found programmed into the SD card storage. It then cross references this information with a database and reports the findings back to you. So if you purchased a 64GB SanDisk, but ChipGenius reports that it’s really an 8GB Emtec, then you know you’ve been had. The advantage of this is that the test process is much quicker, as ChipGenius isn’t reading or writing any data.

Unfortunately, selling fake or counterfeit SD cards is big business. This means that shady sellers are becoming more sophisticated, which allows them to cover their tracks. As a result, ChipGenius won’t be able to sniff out every fake card floating around on the Web, just the poorly programmed ones.

4. Blackmagic Disk Speed Test

If you’re a Mac owner and want to verify your SD cards, Blackmagic Disk Speed Test is for you. This free utility was designed to test the speed of larger drives; however, it will also work as a fake SD card test. The only downside is that Blackmagic Disc Speed Test was designed for people working with large files, such as video clips.

Consequently, the app writes large blocks of data to your storage device and then reads that data to verify performance. Unfortunately, this means that the test takes quite a bit of time to complete.

5. AJA System Test

AJA System Test helps check SD card speed on both Windows and Mac for free. It’s not only simple to use, but also provides detailed graphs to see if performance is consistent or not. If there’s a major fluctuation, there’s likely something wrong with the card. Of course, if you’re testing older cards, this could also be an indicator that it’s starting to go bad.

If you have a new SD card, you shouldn’t see any major fluctuations and the speed should match what’s advertised. Minor fluctuations on the graph are normal as speed varies when adding files. You’ll need to choose the file size to write to your SD card, which means you’ll want to test with an empty card. The larger the file size, the longer the test will take.

6. Speed Out

Speed Out is a super simple portable SD card speed tester. All you have to do is download it and run it directly from the folder. It writes temporary files to your SD card to determine the read and write speeds. It’s only available for Windows. While it’s an older tool, it’s still quite effective for quickly testing SD card speeds without any extra features or settings to deal with.

If you want to see more detail, this probably isn’t the best tool to use. However, if you want something to put on a flash drive to use on various computers, it’s a great option.

7. Flash Memory Toolkit

While Flash Memory Toolkit is a premium tool that costs $39.95, you get an unlimited free trial period where most of the features work with no issues. There’s no credit card necessary to download the trial version. For testing SD cards, you’ll want to use the Low-Level Benchmark tool to see the read and write speeds.

The toolkit is actually a mixture of six tools. You can also use Error Scan and File Benchmark tools to further check if the card has any issues. Fake SD cards often have errors, which reduces the capacity and speed even more. I could use all three of these tools fully in the free trial version.

How can I be sure I’m buying a real SD card?

First, stick with reputable sites and brands. Second, skip deals that sound way too good to be true. Unless it’s a site and brand you trust that’s currently having a major sale, such as Black Friday, you’re not going to get a reliable SD card for 50% off or more. You’re definitely not getting a 256GB SD card for $5 or lower like you might see advertised on Wish.com or similar sites.

Ideally, stick with the following brands:

  • Samsung
  • SanDisk
  • Kingston
  • Lexar
  • PNY
  • Transcend

Avoid buying from third-party sellers. For example, if you’re shopping on Amazon, buy directly from Amazon or the SD card brand’s Amazon store. Amazon is full of fakes, so read the reviews carefully before ordering.

Another option is to buy from a brick-and-mortar store. While you’ll find the occasional damaged card, most are legitimate.

Frequently Asked Questions

Are refurbished SD cards reliable?

Never buy a refurbished or used SD card. This not only opens you up to wasting money on a fake or damaged card, but it could also lead to malware that’s secretly stored on the device.

SD cards wear out over time just like any type of storage device. If it’s refurbished, the life left and storage capacity are significantly reduced and it’s likely been damaged in some way.

Learn more about how SD cards work and how they differ from SSDs.

Is it safe to buy SD cards from Amazon?

Yes. Just stick with authorized sellers. For instance, when I search for a SanDisk SD card, I had numerous results. Some looked almost identical to SanDisk, but were priced much lower. The authorized seller was the listing that said “SanDisk Store” underneath the product name. Plus, it was rated 4.8 out of 5.

Why does my antivirus block some free SD card speed check tools?

Some antivirus tools view any apps that want read/write access to your storage devices as PUPs, or potentially unwanted programs. If you’re ever uncertain about whether an app is safe or not, scan the website and download URLs through VirusTotal. You can also search for “is toolname safe” to see if any other users have had issues with it. All apps on this list have been scanned with VirusTotal.

Image credit: viarami via Pixabay

Crystal Crowder

Crystal Crowder has spent over 15 years working in the tech industry, first as an IT technician and then as a writer. She works to help teach others how to get the most from their devices, systems, and apps. She stays on top of the latest trends and is always finding solutions to common tech problems.

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