Watermark PDF Online – Add Custom Text
Add a visible DRAFT, CONFIDENTIAL or custom text label across your PDF pages. Choose a font style and adjust transparency so the watermark remains readable without dominating the document.
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How to watermark pdf
- Choose a PDF and type your watermark text.
- Select a font style and adjust the opacity.
- Select Add Watermark, then review the downloaded PDF.
What to know before you start
The watermark is placed diagonally on every page. This version supports English letters, numbers and basic punctuation, with up to 60 characters. It does not add image logos or make a document tamper-proof. Input limits are 300 MB and 500 pages.
Frequently asked questions
Which fonts can I use?
Choose Helvetica Regular, Bold or Italic; Times Roman or Bold; or Courier Regular or Bold.
Does a watermark prevent copying?
No. A watermark is a visible label. It does not enforce access restrictions or guarantee ownership protection.
Local processing, no sign-up
HappyPDF processes your selected files in this browser. An internet connection is needed to load processing software. Keep your original document and review the downloaded result; editing can affect forms, annotations and digital signatures.