UD PDF Editor
Add text overlays, highlights, form fills, redactions, and comments to PDFs. The original PDF and edit record are bundled into a tamper-evident .udz — proving what changed and when.
Free · 3/monthLoad PDF
How UD PDF Editor differs from Adobe Acrobat / Smallpdf
Original document hash preserved
The original PDF's SHA-256 is recorded before any edits. The bundle proves the original state — you cannot claim the edited version was always that way.
Edit record is tamper-evident
Every annotation, its type, page, and timestamp are hashed together. The .uds edit record cannot be modified without detection.
No upload required
Processing happens entirely in your browser. Your PDF never leaves your device — unlike Smallpdf, Adobe online, and similar services.
Portable edit audit trail
The .udz bundle contains both the original PDF and the edit record. Anyone can verify what changed without needing access to our service.
No ads. No investors. No agenda.