PDF Fingerprint (SHA-256)
Generate a SHA-256 fingerprint to verify that a document's bytes are identical across copies, or to prove integrity after transfer. Computed locally with the Web Crypto API.
- Processed locally in your browser
- No watermark
- No sign-up
- Works offline
Processed locally in your browser. SHA-256 verifies exact byte identity; it does not embed a recipient tracker or modify the file.
Choose any file or drop it here
Any file type · SHA-256 computed inside a Web Worker
How it works
- 1Drop any file (not just PDFs).
- 2Bytes are hashed inside a Web Worker using SHA-256.
- 3Compare against a known hash or save the checksum.
Your privacy
This tool runs entirely inside your browser using JavaScript and Web Workers. Your document is never uploaded to any server — you can even disconnect from the internet and keep working once the page has loaded.
Frequently asked questions
▸Is this the same as watermark fingerprinting?
No. This computes a byte-exact digest for integrity verification. Invisible per-recipient tracking marks are a separate planned feature.