Sized to each page
The text is sized to span the page, corner to corner when diagonal, whatever the page's size.
Put a word such as DRAFT, COPY or CONFIDENTIAL across your pages, diagonal or straight, in the colour and transparency you choose. The page under it stays readable. Free, in your browser.
How it works
Choose your PDF. It opens in the editor, in your browser.
Type the watermark text, then choose diagonal or horizontal, the transparency and the colour.
Add it to all pages or the ones you choose, and download the PDF.
Why GenPDF
The text is sized to span the page, corner to corner when diagonal, whatever the page's size.
Light, medium or strong transparency in any colour, so the words beneath can still be read.
Write the watermark in Arabic, French or any script: it is drawn with a font that has its letters.
Questions
Yes. Choose all pages, the current page, or a list such as 1-3, 5.
Yes. Choose Picture (PNG or JPEG) as the watermark type, then its width as a share of the page, its opacity and its place: centred, at an edge or a corner, or repeated across the page, on the pages you choose. Each copy stays a picture you can move or delete before you download.
It is written into the page itself, not laid on top as a comment, so a reader can't simply hide it. A PDF editor can still change it, as it can any text.
No. The watermark is added in your browser. A scanned page is sent as an image only if you agree to have its words read, and deleted as soon as they are read.