Sign a document. Anyone can verify it.
Fast Sign signs any file with your Fast address and records that signature on-chain (fast:testnet) — so anyone can later confirm who signed it, when, and that the signed original hasn't changed. Your file never leaves this page; only its fingerprint is published.
Sign any file
Sign any file in your Fast Wallet — its fingerprint is settled on-chain. A PDF can also get a visible stamp (a QR linking to its on-chain record) and a downloadable signed copy.
Sign a documentVerify any file
Drop any file — or paste its fingerprint — to see every on-chain settlement recorded for it. A signed PDF also shows its embedded signature receipts, confirmed against their Fast settlements.
Verify a document