Notarize

proof of existence
Prove a file existed — exactly as it is — on a certain date. Its fingerprint is stamped on-chain forever. Later, anyone can check the same file against that stamp.

Your file never leaves this device. We only read it to compute a fingerprint (a SHA-256 hash) right here in your browser. Only that 64-character fingerprint is ever sent on-chain — never the file, never its contents.

Choose a file
document, image, PDF, anything — up to ~50 MB
— or paste text —
Fingerprint · SHA-256

Notarize proves a specific file existed, unchanged, at the stamped time. It does NOT prove who authored it, who owns it, or any legal right over the content — only that this exact file existed by then. Change one byte and the fingerprint changes. Each stamp is permanent and cannot be removed. Not legal advice.

domburns.xyz · stamped on the Internet Computer