PDF Watermark
Stamp a diagonal text watermark on every PDF page — control opacity, angle, and color. No upload.
Examples
Confidential stamp
Input
contract.pdf + CONFIDENTIAL, 15% opacity
Output
Every page marked diagonally
Draft review
Input
proposal.pdf + DRAFT, grey, 45°
Output
Subtle grey diagonal across each page
Company branding
Input
report.pdf + Company Name, 10% opacity
Output
Light brand watermark on all pages
About this tool
This free PDF watermark tool adds a diagonal text stamp to every page of your document — entirely in your browser, with no upload. Choose the text, font size, opacity, rotation angle, and color, then download the watermarked PDF. Because everything runs on your device, your documents stay completely private.
How to use
- Drop a PDF file onto the uploader or click to browse.
- Type your watermark text or choose a preset (CONFIDENTIAL, DRAFT, SAMPLE…).
- Adjust font size, opacity, angle, and color to your preference.
- Click Apply Watermark and download the result.
Tips for a good watermark
A low opacity (10–20%) keeps the document readable while clearly marking it. Grey text is less distracting than black for draft reviews. A 45° angle is the standard diagonal look; 0° gives a straight horizontal stamp across the center if you prefer that style. Keep the original unwatermarked file — once applied, the watermark cannot be removed from the output.
Frequently asked questions
How do I add a watermark to a PDF?
Drop your PDF onto the tool, type the watermark text, adjust the font size, opacity, angle, and color, then click Apply Watermark. The watermark is stamped on every page and you can download the result.
Is this watermark tool free?
Yes — completely free with no sign-up, no upload, and no limit on pages. Everything runs in your browser.
What watermark text can I use?
Any text up to 60 characters. Common choices are CONFIDENTIAL, DRAFT, SAMPLE, or INTERNAL USE. You can also type custom text like your company name or a date.
Can I control the opacity of the watermark?
Yes. Use the Opacity slider (5%–80%) to set how visible the watermark is. Lower opacity (around 10–20%) creates a subtle background stamp without obscuring the document content.
Are my PDF files uploaded to a server?
No. The watermark is applied entirely in your browser using pdf-lib. Your file never leaves your device.
Does the watermark appear on every page?
Yes. The tool automatically stamps the watermark in the center of every page in the document.
Can I remove the watermark later?
No. Once the watermark is baked into the PDF, it is part of the document content and cannot be removed without the original unwatermarked version. Keep the original file if you may need an unwatermarked copy.
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