Add Watermark to PDF Online Free
Stamp custom text over your PDF in seconds. Choose typography, diagonal angle, transparency, and color. 100% private client-side processing in your browser with zero server uploads.
Click to select file or drag & drop here
Supported formats: application/pdf • Processed 100% locally in your browser
How to Use Add Watermark to PDF Online
Upload PDF
Select the PDF file you want to brand or mark with a watermark.
Customize Watermark Text
Enter your text (e.g. CONFIDENTIAL), pick color, opacity (10%–90%), font size, and diagonal/center placement.
Apply & Download
Download your watermarked PDF immediately.
Frequently Asked Questions — Add Watermark to PDF
Can I make the watermark semi-transparent so text underneath stays readable?
Yes, use the Opacity slider (default 25%) so your document text remains crystal clear.
Can I place the watermark diagonally across the center?
Yes, choose 45° Diagonal Center, Horizontal Center, Header, or Footer placement.
Is the watermark applied to all pages?
Yes, or you can specify a custom page range.