Verify TamperKit Proof

Paste the full proof block from the document, everything between the BEGIN and END lines, to see the complete verified record.

Check a Photo or Video From the PDF

A TamperKit proof PDF lists the SHA-256 fingerprint of every photo or video attached at activation. Drop the file below to compute its SHA-256 in your browser and compare it to the fingerprints printed in the PDF. The file is never uploaded.

Drag a file here, or tap to choose.

To check by hand instead, run shasum -a 256 yourfile (macOS, Linux) or certutil -hashfile yourfile SHA256 (Windows). The output must equal a fingerprint in the PDF. Tip: paste the proof block above first and the comparison runs automatically.

Official verification runs on validate.nfcmint.com. No app or account required.