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Get the free OSDF Viewer

The OSDF Viewer opens and verifies documents anywhere - online or fully disconnected. Every release is signed, reproducible, and recorded in the public transparency log, so you can verify exactly what you run before you run it.

OSDF Viewer

Free to download. Free to verify.

The Viewer is the downloadable OSDF app. Authoring tools run in the browser, and developer tooling is open source.

Coming soon

Desktop Viewer

Open and verify OSDF documents on macOS, Windows, and Linux - fully offline.

macOSWindowsLinux
Web

Browser Viewer

Open .osdf files with the same dark UI as the site. Requires Microsoft Entra sign-in - available to customer and admin portal roles.

Launch viewer
Enterprise endpoint

Companion Agent

The local trust broker that enforces document access policies at the edge. Signed installers for Windows, macOS, and Linux with SHA-256 checksums and MDM deployment packages.

No install needed

Prefer to stay in the browser?

Create, view, and verify documents on the web.

Sign-in

Web Viewer

Open and verify .osdf files in your browser - Entra sign-in required. Same local WASM engine as the public verifier.

Launch viewer

Web Editor

Create, sign, and convert documents right in your browser - nothing to install.

Launch web app

Verify online

Run the full verification pipeline in your browser without downloading anything.

Verify a Document
Developers

Verification CLI - open source

The reference core and CLI live in the open. Install from a package manager or build from source, then verify the binary against the transparency log.

  • Open source in the osdf-systems/osdf repository
  • Signed & reproducible release builds
  • Logged in the public transparency log
View osdf-systems/osdf on GitHub
install & verify
# install from a package managerbrew install osdf-systems/tap/osdf # verify the binary against the transparency logosdf self verify $(which osdf) osdf verify ./document.osdf
Release notes

Viewer version history

Synced automatically from GitHub releases - refreshed every hour.

v0.4.2LatestFeb 1, 2026View on GitHub
  • Faster local verification (0.2–0.6 ms typical)
  • Improved offline trust-evidence handling
  • Accessibility and rendering fixes
v0.4.0Jan 1, 2026View on GitHub
  • Witness cosignature verification in the Viewer
  • Expanded transparency-log checks
  • Performance improvements on large documents
v0.3.5Dec 1, 2025View on GitHub
  • Hardened constrained-ZIP parser
  • Consistency-proof caching
  • PDF/A rendition fidelity improvements
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The future of trusted documents

Bring cryptographic verification, verifiable provenance, and zero-trust access control to every document your organization creates and receives.