Check an exact file
Does this copy
carry their Mark?
Drop the original file to look for a signed record from a verified account. The fingerprint is made in your browser; the file never leaves your device.
Drop any file here, or click to choose
Hashed locally. Your file never leaves this page.
What a Mark can tell you
Who signed it
Every Mark is bound to an account and signed with a key only the service holds. A Mark asserts provenance from a signer at a moment in time. It does not claim to prove ground-truth authorship.
When it existed
After daily anchoring completes, the Arweave record provides an independent upper bound on when the fingerprint existed. The signing time remains the service's claim. Base is an optional additional witness.
Forever, without us
Keep the original file and download the bundle after anchoring. Its signature and Merkle path can be checked offline without Mark. Independently checking the public anchor requires ledger access.