Watermark PDF stamps a word, a phrase or an image onto the pages of a PDF. Type something like DRAFT or CONFIDENTIAL, or pick a PNG or JPG logo, then set the size, color, opacity and angle. Place it once per page in any of nine positions, or tile it across the whole page. The mark can go on every page or only the pages you choose.
The watermark is written directly into the PDF's page content by JavaScript running in your browser; a text mark uses the standard PDF fonts (Helvetica, Times and Courier) that every reader already has. The file never leaves your device: nothing is uploaded, there is no queue and no account, and the result downloads straight from the tab. Files up to 100 MB, one at a time.
Two things to know before you start. The mark is drawn on top of the existing page content, not behind it, so at full opacity it will cover whatever is underneath; the default 25 percent opacity keeps the page readable. And the built-in fonts only cover Latin characters, so text in Arabic, Chinese, Hindi or any other script has to go in as an image using the Image option.
How to use Watermark
- 1Click Select file, or drop the PDF onto the page.
- 2Under Watermark type, pick Text and type your wording (DRAFT is filled in to start), or pick Image and choose a PNG or JPG file.
- 3Adjust the look: Font, Size (pt) and Color for text, Width (% of page) for an image, then Opacity (%) and Angle (degrees) for either. The defaults are 25 percent opacity at 45 degrees.
- 4Under Layout, choose Once per page, pick a Position on the nine-cell grid and set the Margin (pt) from the page edge, or choose Tiled across the page to repeat the mark over the whole sheet.
- 5Under Watermark these pages, keep All pages or switch to Chosen pages and enter a list such as 1-3, 5 or 2-last.
- 6Click Add watermark, then click the Download button. The file is saved under the original name with -watermarked added.
Frequently asked questions
- Is my PDF uploaded to add the watermark?
- No. The watermark is drawn into the file by JavaScript running on your own device, and the download comes straight from your browser. Nothing is sent to FreeAIPDF or anyone else.
- Can I put the watermark behind the page content instead of on top?
- No. The mark is always drawn over the existing content, because placing it underneath would mean rewriting each page's own drawing instructions. Keep the opacity low, around the default 25 percent, and the page stays readable with the mark showing through.
- Can I watermark only some of the pages?
- Yes. Under Watermark these pages, choose Chosen pages and type a list using commas and ranges, for example 1-3, 5, 8-10. The word last stands for the final page, so 2-last skips the cover.
- Does a watermark stop someone from removing it or copying the document?
- No. It is a visible mark written into the page as ordinary content, so anyone with a PDF editor can take it out, and a text watermark may even show up when a reader selects or searches the page text. If you need to control who can open the file, use Protect PDF to add a password.
- Can I use a logo with a transparent background?
- Yes. Choose Image and pick a PNG with transparency; the transparent areas stay clear, and JPG works too if you do not need transparency. Width (% of page) sets how wide the logo is relative to the page, and its proportions are kept.
- Why do I get an error about Latin characters?
- The text option uses the standard PDF fonts (Helvetica, Times Roman and Courier), which only cover Latin characters. For text in another script, make an image of the wording, ideally a transparent PNG, and add it with the Image option instead.