Add Watermark
Add a text watermark to all pages — CONFIDENTIAL, DRAFT, or custom text. Runs entirely in your browser.
About this tool
Add a diagonal text watermark to every page of any PDF. Common uses: marking documents as CONFIDENTIAL before sharing, adding DRAFT or SAMPLE labels to work-in-progress files, or branding documents with your company name. The watermark is drawn at -45° across the center of each page using Helvetica Bold. Choose from light gray, red, or blue colors and adjust font size from 12 to 200 points. Uses pdf-lib's text drawing API entirely in your browser. No upload, no sign-up, no watermark restrictions.
How to use it
Quick steps to get the most out of this utility.
- 1
Drop your PDF
Any size up to 100 MB.
- 2
Set watermark text
e.g. CONFIDENTIAL, DRAFT, SAMPLE.
- 3
Choose size & color
Visible but not obstructive.
- 4
Add & download
One click, watermarked on all pages.
Mark documents with visible labels
Watermarks serve two purposes: they communicate document status (DRAFT, CONFIDENTIAL, FOR REVIEW) and they deter unauthorized redistribution by making the document visibly marked. This tool adds a diagonal text watermark across every page of your PDF, drawn directly into the content stream so it appears in any PDF reader.
Why no upload matters
If you are watermarking a confidential document, the last thing you want is to upload it to a server. Toolisk draws the watermark locally in your browser — the file never leaves your device. Your content stays private.
Frequently asked questions
Is this safe? Does it upload my PDF?+
No upload whatsoever. The watermark is drawn using pdf-lib entirely in your browser. Your PDF never leaves your device.
What is the maximum file size?+
PDFs up to 100 MB are accepted. Files over 30 MB may be slower on mobile due to per-page text rendering.
Does it work offline?+
After the page has loaded once, yes — pdf-lib is cached and watermarking runs locally.
Will this work on iPhone / iPad?+
Yes, on modern iOS Safari.
What text can I use as a watermark?+
Any text — common choices include CONFIDENTIAL, DRAFT, SAMPLE, DO NOT COPY, or your company name. Font is Helvetica Bold for visibility.
Can I customize the appearance?+
Yes — choose font size (12–200), color (light gray, red, or blue), and the text itself. The watermark is drawn at a -45° angle across the center of each page.
Is the watermark permanent?+
The text is drawn into the PDF content stream of each page — it becomes part of the page like any other drawn text. It cannot be removed without editing the content stream.
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