Why add a watermark
A watermark tells every reader what a document is: CONFIDENTIAL, DRAFT, COPY, SAMPLE or the name of your company. It discourages people from passing on drafts as final versions and makes it clear who a document belongs to when it is shared.
How the settings work
Type your text (up to 80 characters), then choose the position — Diagonal, Center, Top, Bottom or Tiled across the whole page. Set the font size (default 60), opacity (default 30%) and colour, and choose all pages or only the pages you type. The watermark is added on top of the page content.
Choosing a good style
Diagonal and tiled watermarks are the hardest to crop or cover. Light grey or red at 20–30% opacity stays visible without making text hard to read. Short words such as DRAFT or COPY work better in large sizes than long sentences.
Common problems and how to fix them
Text underneath is hard to read: lower the opacity or font size. The watermark covers a signature or stamp: choose Top or Bottom instead of Center. Only some pages need marking: type those page numbers in the Pages box.
Good habits
Keep an unwatermarked original for yourself, use consistent wording across your documents, and remember that a watermark discourages copying but does not make a PDF impossible to edit.