Drop a file. Get a proof. 5 seconds.
No upload. No sign-up. No catch.
Drop a file here, or click to browse
Any file. Anything you make.
Nothing uploads. Everything happens in your browser.
- Hashed in your browser with the Web Crypto API.
- We never see your file or its contents.
- Anyone can verify your proof against the file.
It doesn't do everything. It creates everything that does.
Common questions
- Is my file uploaded anywhere?
- No. The file stays in your browser. We use the Web Crypto API to compute a SHA-256 fingerprint locally; only that fingerprint is signed.
- What does the proof contain?
- Filename, SHA-256 hash, byte size, an ISO 8601 UTC timestamp, the algorithm name, and a scheme tag. No file content. Download the JSON to see the exact shape.
- Can I verify the proof later without you?
- Yes. The proof is just a JSON file with the hash and timestamp. Anyone with the original file can recompute the SHA-256 and confirm the match. We are not in the loop.
- Is it really free?
- Yes. The browser-based Try flow is free forever. There is no sign-up wall and no credit card. The Free tier on the dashboard adds 3 permanently-saved proofs per month at no cost.