Add PDF Watermarks Locally — Your Document Never Leaves Your Device
Watermarking is a common step for document sharing — DRAFT, CONFIDENTIAL, DO NOT COPY. The irony of most watermark tools is that you upload a confidential document to a stranger's server in order to stamp it as confidential. OfflinePDF breaks that contradiction. The pdf-lib engine renders your watermark text across every page inside your browser's JavaScript runtime. Nothing is transmitted. Your marked-up document downloads directly from the browser to your disk.
📝 Customisable Text
Set your own watermark text, choose the font size, opacity, colour, and diagonal angle.
👁️ Live Preview
See exactly how the watermark appears on a sample page before applying it to the full document.
🔐 Handle Confidential Docs Safely
Stamp CONFIDENTIAL or DRAFT on documents without ever uploading them — the only logical approach for sensitive files.
🆓 No Restrictions
No character limit on watermark text, no cap on page count, no account required.
OfflinePDF vs Typical Online Tools
Feature
OfflinePDF
Typical Online Tools
Uploads your PDF
Never
Always
Custom text + opacity
Yes
Varies
Works without internet
Yes
No
Output watermark from tool
Never
Free tiers often add their own
No account required
Yes
Often required
Frequently Asked Questions
Yes. The watermark is applied uniformly to every page in the document in a single operation.
Yes. Adjust the opacity slider to set how transparent the watermark appears behind the page content.
A text watermark is a visual layer only. For copy and edit protection, combine the Watermark tool with the Lock/Unlock tool.