How do I add a watermark to a PDF?

Select your PDF file, choose either Text or Image watermark, adjust the position, opacity, and rotation angle using the live visual preview, then click 'Download Watermarked PDF'.

Can I add a tiled mosaic watermark across the entire page?

Yes! Check the 'Repeat mosaic pattern across page' toggle to create a high-security repeating diagonal watermark across all pages.

Can I watermark with my company PNG logo with transparent background?

Yes. Switch to the 'Image Watermark' tab and upload your transparent PNG logo. You can adjust the scale, opacity, and position freely.

Watermark PDF Documents

Stamp confidential text notices, copyright warnings, or corporate logos onto your PDF pages with real-time interactive preview. 100% private in browser memory.

Select PDF file

or drag and drop PDF here to configure watermark stamps

Live Page 1 Preview

How to Add Text & Logo Watermarks to PDF Online

01. Upload PDF

Drag and drop your file into the secure in-browser RAM sandbox with zero server uploads.

02. Customize Stamp

Type your watermark text or upload a transparent PNG logo. Adjust opacity, angle, and 3x3 position with live preview.

03. Download PDF

Click "Download Watermarked PDF" to embed high-fidelity vector text stamps across all chosen pages.

Watermarking FAQs

Can recipients easily remove the watermark?

Our tool embeds the watermark into the document's permanent content stream. Combined with DocumentAlter's Protect PDF tool, you can restrict editing permissions to prevent removal.

Does the watermark affect existing PDF links or bookmarks?

No! PDF-Lib preserves existing hyperlinks, document outline bookmarks, and vector annotations while adding the watermark layer.