OpenProofProof
without
surrender.
A file fingerprint. A blockchain timestamp. No uploads, no accounts, no backend. OpenProof registers a SHA-256 hash on Base Sepolia. The file never leaves your browser.
How it works
01
Choose a file
Select any file from your device. It is read locally and never uploaded.
02
Register the hash
OpenProof hashes the file with SHA-256 in your browser. Connect a wallet and write only that 32-byte hash to the Base Sepolia registry.
03
Verify forever
Anyone can re-hash the file and check whether the fingerprint exists onchain. No wallet needed. No login. No fee.
Registry
0x60d3DD631E6e4F6D76f761689d6FA229945a874aBase Sepolia84532OwnerlessOpenProof is proof-of-existence infrastructure. A SHA-256 fingerprint on Base Sepolia. No backend, no database, no tracking. Just a hash onchain.