Free tool

Digital fingerprint of an exhibit

Work out the SHA-256 of a file and produce the chain of custody record, with its size, the date and your description.

The file never leaves your computer. The fingerprint is worked out by your own browser and is not sent to any server, ours or anyone else's. You can check it: disconnect from the internet and the tool still works.

Drop the file here

What it is for

Showing that a copy is identical to the original: if the two fingerprints match, the files are the same, bit for bit.
Showing that an exhibit has not been altered since it was collected, even if it has passed through several hands.
Checking the file handed to you by a party against the one recorded in the police report or in the court record.
Recording the moment you had the file and the state it was in.

Both SHA-256 and SHA-1 are worked out. The first is the one in use today; the second still appears in older police and court records and is needed to check against them, even though it is no longer considered safe against deliberate tampering. A fingerprint proves integrity, not authenticity: it says the file has not changed, not where it came from.

And the exhibit, in its case file

Gest Peritia works out and keeps this same fingerprint for every document you add to a case file, next to the deadlines and the report that cites it.

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