Watermark PDF
Stamp a diagonal watermark like CONFIDENTIAL or DRAFT across every page of a PDF. Free and private.
Free · No sign-upHow to use Watermark PDF
- 1. Type your watermark text — for example CONFIDENTIAL, DRAFT or COPY — in the Watermark text box. If you leave it empty, the word WATERMARK is used.
- 2. Set the Opacity slider between 5% and 60% (20% by default) so the stamp is clearly visible while the page text underneath stays readable.
- 3. Drop your PDF into the upload box. The text is stamped diagonally across the middle of every page in gray bold letters sized to fit, including landscape and rotated pages. Accented, Vietnamese, Polish and Cyrillic text works too.
- 4. Click the download button on the result card to save the copy with -watermarked added to its name. To change the text, adjust it and drop the PDF again.
Frequently asked questions
Is it free to watermark a PDF online here?
Yes, it’s free with no sign-up and no GrabCast branding added. The tool sets no page limit; every page in the document gets the watermark. Very large PDFs simply take a little longer because they’re processed on your own device.
Is my PDF uploaded when I add a watermark?
No. The PDF is opened and edited with the pdf-lib library right in your browser, and the watermarked copy is saved directly to your device. Your document never reaches GrabCast’s servers, which matters for confidential files.
How do I add a CONFIDENTIAL or DRAFT watermark to a PDF?
Type the word in the Watermark text box, pick an opacity (the default 20% keeps text readable), and drop the PDF in. Each page gets the word in large gray bold letters running diagonally across the middle, sized to fit the page and turned the right way on landscape or rotated pages. Download the new copy and share it instead of the original.
Can someone remove a watermark from my PDF?
This tool adds the watermark as a semi-transparent text layer on each page, which deters casual copying and makes the document’s status obvious. Someone with a full PDF editor could still delete it, so for stronger protection also restrict who receives the file or add a password.
Why does my PDF fail to get a watermark?
Encrypted or password-protected PDFs can’t be opened for editing, and damaged files may not load; you’ll see “Could not process this PDF.” Remove the password in the app that created it and try again. Watermark text in Latin, Vietnamese, Polish and other accented alphabets, Greek or Cyrillic works; Chinese, Japanese, Korean, Arabic, Hebrew, Hindi and emoji characters aren’t in the font yet, so the tool warns you and leaves them blank.
Will a watermark change the text or layout of my PDF?
No. The original pages, text, images and links are kept, and the watermark is simply drawn on top. Because the watermark is real text — Helvetica Bold, or the free Noto Sans Bold font for accented and Cyrillic letters, embedded with only the characters used — the file stays searchable and usually grows only slightly in size.