Authenticity check
Verify a GPS Camera photo
Enter the code printed on the photo’s stamp. You’ll see the time and place the camera signed, and whether the picture is anchored in the Bitcoin blockchain.
The code looks like GC-7K3M-Q9XW. Scanning the QR code on the stamp brings you straight here.
- Signed on the phone
- Anchored in Bitcoin
- Photos never uploaded
How verification works
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Step 1
Signed on the phone
When the photo is taken, the app signs the time, GPS position and a fingerprint of the image with a key locked inside the phone’s secure hardware.
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Step 2
Anchored in Bitcoin
The file’s fingerprint is timestamped with OpenTimestamps and sealed into a Bitcoin block, so nobody can change it later without it showing.
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Step 3
Checked in your browser
Every check runs on your own device. You don’t have to trust this website, and photos you check are never uploaded.
Verify code
What the camera recorded
Checks
Is your copy the original file?
Choose or drop the photo or video. It is fingerprinted (SHA-256) on your device and never uploaded.
What this does and doesn’t prove
- The Bitcoin timestamp proves the saved file existed no later than the block’s time, and that it hasn’t changed since. It can’t prove when the photo was taken before that.
- The signature proves the record was signed by one particular phone key (fingerprint shown above) and hasn’t been altered. It identifies a key, not a person; anyone can install the app.
- Time and place are what that phone reported. GPS and the clock can be faked on a tampered or rooted phone. Keys kept in a security chip (“StrongBox”) are the hardest to misuse.
- A copy that doesn’t match isn’t necessarily fake: messaging and social apps re-compress pictures. Ask for the original file to check it.