True SD Card Capacity & Speed

Alan Robinson

About this app

This "short" endurance test confirms if your SD card is valid and reliable OR if it's a counterfeit that has way less storage space than advertised. It fills your card with carefully designed files that the app can then verify to ensure that what's written to your flash card can be read back reliability. It also measures read & write speed at the same time, because, why not?

It's not the most pretty app because the focus has been instead on real-world testing and good algorithms. It is, however, easy enough to use. The only way to know your card is good is to fill it to the advertised capacity. Typically this takes less than an hour but can be longer if the card is particularly slow or enormous. Piece of mind is worth the wait and there are no shortcuts to it!

You can also test your phone's internal storage. With USB-OTG you probably can test thumb drives too, depending on how your phone works.

Note: English only. The default settings are reasonable, however, so you may just proceed to "start test".

Ratings and reviews

I am so glad I ran this test! I bought a cheap SD card from Amazon. I didn't know any better. It was a total accident that I found out about fake SD cards. I was just comparing brands to figure out which one to buy & came across the info. (Thanks, Google!) I went ahead and got one just to find out for myself. Phone read it as a 1 TB card. The test found that nearly 75% of the written files became corrupted. This app saved me from likely losing countless priceless memories!!

As most of the reviews say, this app is very easy to operate. I made the mistake of not switching from internal to external test. I just bought a cheap 128 GB card on temu. The internal was much smaller & more than already half used. So I wound up with a test that said 19GB & lol, I was this close to calling the seller a thief & asking for refund. I figured out my mistake & switched to SD card & test was successful. Yay! It took approx 75 min on network 4g/5g. It's ALL GOOD! 100% recommend!

Barebones and straight to the point. It only fills a SD card with temporary files while recording read/write speed, verifies that they are real and not corrupted, and guides you on how to clear up said temp files to actually use your (hopefully) authentic and properly functioning SD Card. I have a tip,you can remove battery optimisations in the settings to run it in the background. In the case that it does restart, you can just pick up from where you left it from.

What’s new

Now with android 14 support.