Proof that doesn't depend on trust.
Anchor the fingerprint of your digital records on-chain without exposing the underlying data. Prove it existed. Prove it wasn't changed.
How it works
Four steps to undeniable proof
01
Create
Upload a file or paste a text record. It never leaves your browser.
02
Hash
SHA-256 runs locally and produces a unique 64-character fingerprint.
03
Anchor
Only that fingerprint is sent to the smart contract in one transaction.
04
Verify
Anyone can re-hash the original and compare it with the on-chain proof.
Why ProofFlow
Verifiable without exposing anything
Privacy-first
Raw files stay off-chain, on your device. The chain only ever sees a hash.
Tamper-evident
Change one byte and the hash changes completely. Modifications can't hide.
Blockchain-backed
Anchored with a timestamp and creator address no single server can rewrite.
Publicly verifiable
Share a link. Anyone can verify independently — no account, no permission.
No trusted third party
Verification is math plus an open ledger, not a company's promise.
Example use cases
Built for moments that must hold up later
Document verification
Prove a contract, certificate, or policy existed in an exact version.
Project milestones
Timestamp deliverables so completion dates are beyond dispute.
Digital approvals
Anchor who approved what, and exactly which bytes they approved.
Academic artifacts
Theses, datasets, and lab records with independently checkable integrity.
Software releases
Bind a version string to a build hash customers can re-verify.
Ownership records
Link a creative work's fingerprint to your wallet address.