Proof of existence — free, hash-only

Prove your document existed today,
without showing it to anyone.

Drop any file or paste any text. It is hashed in your browser — the content never leaves your device. Only the 64-character SHA-256 fingerprint is anchored to a public registry with a timestamp. Anyone holding the same document can verify it forever; nobody can reconstruct it from the hash.

Drop a file here or click to choose
Read locally · never uploaded · any size, any type

— OR PASTE TEXT —

Anchored

Your receipt

SHA-256
Anchored at
Label
Open the public verify link

Keep the original document safe — the anchor proves a document with this exact fingerprint existed now; only the original file can reproduce the fingerprint. Change one character and the hash breaks.

What this is — and is not. Anchoring proves a document existed, unchanged, at a point in time. It is not a clinical signature, not a copyright registration, and not legal advice. Every day the whole registry’s root is countersigned into Bitcoin via OpenTimestamps — your proof survives even if hashcare disappears. Physician-signed clinical attestation is a separate rail — see verify and the review network.