Free Online Watermark PDF
Add a text or image watermark to every page of a PDF.
Upload a PDF to see its page count.
Latin characters only with the standard PDF font. Keep it short for a clean diagonal stamp.
Choose a PNG with transparency for the best logo result. JPG images include their background.
Upload a PDF to begin.
Size is relative to the page width: 10% is about 60 points on an A4 page. The watermark is drawn over the existing page content, so choose a light opacity when the document contains dense text. The source file is never modified.
About the Watermark PDF Tool
A watermark communicates ownership, confidentiality, or status without hiding the page underneath. This tool applies a text stamp or a logo image to every page of a PDF. You control the position, opacity, rotation, and size, so the mark can be a subtle diagonal note or a bold centered logo. All processing happens in your browser.
Text watermarks
Text watermarks are drawn with the standard Helvetica Bold font. They are real text in the PDF content stream, which means they print crisply and scale without pixelation. The standard font covers Latin characters; accents and common Western European letters work, but scripts such as Arabic, Chinese, Japanese, or Cyrillic are not supported without an embedded custom font. A rotation of -45 degrees creates the familiar diagonal stamp, while 0 degrees places the text straight across the page.
Image watermarks
PNG and JPG images can be used as a logo or seal. PNG transparency is preserved, so the page shows through the transparent areas. A JPG watermark carries its own rectangular background, which is usually visible unless the image matches the page color. The size slider sets the image width as a percentage of the page width; very tall images are automatically reduced so they still fit vertically. Opacity applies to the whole image, including its transparent parts.
Frequently asked questions
Can I remove a watermark later?
This tool adds the watermark to the page content, so removing it requires a PDF editor or restoring an earlier copy. Always keep the original file before watermarking a document you may need to reuse.
Why does my text watermark show an encoding error?
The built-in Helvetica font supports Latin characters only. If you enter characters from another script, the PDF library cannot encode them. Use an image containing the text instead.
Does watermarking reduce the quality of the original pages?
No. The watermark is drawn as an additional object on each page. Existing text, images, and vector graphics are left untouched.