PDF Integrity Hash (SHA-256) — free, private, in your browser

Compute a SHA-256 fingerprint to prove a file is unchanged. Unlike iLovePDF or Smallpdf, nothing is uploaded: the processing happens on your own device, so the tool works even with the Wi-Fi off.

PDF Integrity Hash (SHA-256) now — no sign-up →

How it works

  1. 1Drop a PDF onto the page
  2. 2Read the SHA-256 fingerprint
  3. 3Compare it any time to detect tampering

Questions

Are my files uploaded?

No. CommandEditor runs entirely in your browser with WebAssembly — your file never leaves your device. You can verify it: open your browser's network inspector, or switch off Wi-Fi after the page loads; the tool still works.

How do I prove a document existed at a point in time?

Pair the hash with the Notarize tool to anchor it to the Bitcoin blockchain via OpenTimestamps — independently verifiable forever.

Related tools

CommandEditor is open source and free forever. 114 tools, 60+ voice commands, on-device AI — your files never leave your device.