True SD Card Capacity Test +

4.6
188 reviews
1K+
Downloads
Content rating
Everyone
Screenshot image
Screenshot image

About this app

This "short" endurance test confirms if you 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. You can leave it running overnight. 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 some phones will let you test thumb drives too, but many phones don't follow the spec properly and don't give access to the OTG drives.

Note: interface is in English only.
Updated on
Aug 14, 2025

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
No data shared with third parties
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No data collected
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Ratings and reviews

4.6
161 reviews
Lorne Fenna
September 28, 2025
I ordered a couple of cheap 256gb SD cards from Amazon, then began regretting my decision to go cheap. I downloaded this app to test them for peace of mind, and found they corrupted 25% of data written to them. I've returned the cards, I have no regrets about buying this app for a dollar
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Jack Night
April 14, 2022
When I tried out the free version it told me I had LOTS AND LOTS of problems with my new SD card on my phone. I went ahead and purchased the full version to more closely examine the problems and it was "amazing" that all of the problems had disappeared, all I had to do was pay and it was magically fixed. I can't say for certain it's a scam...but I won't buy anything from him again and am deleting the program just in case it has a vindictive nature.
21 people found this review helpful
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Alan Robinson
April 16, 2022
The two versions are identical in their testing method, there is no "magic fix". Something changed on your end, perhaps a removal and insertion of the card (which cleaned the contacts), etc.I would hesitate to use the card that is "fixed" as you stated. There is something failing intermittently in your setup, which makes diagnoses very difficult.
A Google user
November 10, 2019
Performs as advertised. Not a fancy UI, but clear enough. When 1st used, analysed my phone's internal memory instead of the SD card. Emailed the author and he very quickly explained this can happen & app can be directed to analyse the card. Nervous about the real size or speed of your SD card? Buy this! It gets the job done and author provides excellent support.
30 people found this review helpful
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What’s new

Full android 16 support.