Check a CaseGuardian™ record
Everything on this page runs inside your browser. Nothing you choose or paste is sent to CaseGuardian™ or anyone else: the page is built so it cannot make network requests. No account is needed.
1. Fingerprint a file
Choose a photo, video, audio or document file from a CaseGuardian™ export or share. This page computes its SHA-256 fingerprint on your device and compares it with the fingerprint listed for that file in the export or on the share page (Files in this production table).
The fingerprint is shown in two forms. Files captured in the CaseGuardian™ mobile app are fingerprinted over the file’s base64 text; files hashed in a web browser are fingerprinted over the raw bytes. A match with either form is a match.
2. Check a device signature
Each sealed entry’s fingerprint is signed with an Ed25519 key created on the device that recorded it. Paste the entry’s SHA-256, its signature and the device’s public key (all three are listed on the share page and in the export). A valid result means that key signed that exact fingerprint. It does not identify a person.
3. Check the Bitcoin timestamp
Each entry’s fingerprint is submitted to OpenTimestamps, which anchors it in the Bitcoin blockchain through public OpenTimestamps calendars. The export contains one .ots proof file per entry in ots_receipts/. This page does not check .ots files: checking one needs Bitcoin block data. Use the free, independent verifier at opentimestamps.org or the ots verify command-line tool. A confirmed proof shows the fingerprint existed at or before the time of that Bitcoin block.
How the fingerprints are defined
The exact formulas are published in the CaseGuardian™ Cryptographic Practice Statement, version 1.0.