Guide

Add a watermark to a PDF

A watermark is a repeated mark that says something about the whole file: DRAFT, COPY, CONFIDENTIAL, or your name and a date. It is not a signature. Signatures go on a line once. Watermarks sit behind or across every page so a screenshot still carries the notice. Use Watermark PDF for that job.

Pick words a later reader will understand

Short words work. “DRAFT 26 Sep 2026” is clearer than a paragraph. If you are sending a copy of an original you still hold, “COPY — original retained” stops someone treating the PDF as the wet-ink document. Avoid putting a bank account number or a home address in the watermark. The point is a status mark, not extra personal data on every page.

Keep the text underneath readable

Low opacity and a diagonal placement miss most body text. A heavy black bar across the middle fails the “can I still read the contract” test. Check a page with a table and a page with a signature. If either is hard to read, lighten the mark. Image watermarks (a logo) should be simple; a photo logo turns into noise after the file is compressed.

When a watermark hurts you

Do not watermark the copy you file with a court, a tax office, or a school admissions portal unless they asked for it. Many of those systems treat extra marks as alterations. Keep a clean filing copy and a watermarked copy for emailing to people who should not treat it as final.

Watermarking does not encrypt the file. Anyone can still copy the text. If you need actual access control, that is a different product. If you only need a visible name on a signature line, use the signature maker instead.

Updated September 26, 2026. First published September 26, 2026.

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