How to add a watermark to a PDF

Identify drafts or copies with a readable notice and understand its limits as a protection measure.

A visual notice with one clear purpose

“DRAFT”, “COPY” or “INTERNAL USE” explains the document’s status. Keep it brief; up to 60 characters are allowed, but one or two words are usually clearer.

A watermark does not encrypt a file, block printing or prove authenticity. “CONFIDENTIAL” does not control how the copy is shared. It cannot replace digital signatures or access controls.

Position, size and opacity

A central diagonal stands out; a top or bottom position is more discreet. For one word on A4, try 40 to 52 points and 20% opacity. Adjust after checking tables, signatures, stamps and dark backgrounds.

Low opacity lets the background remain readable. Transparency does not fix a poor position. Check landscape and rotated sheets too: placement follows visible orientation.

Apply it to the final version

Merge, reorder and delete pages; correct orientation and add numbering before applying a watermark. Pages inserted later may lack the notice.

  1. Load the PDF and enter your text.
  2. Leave selection blank for all pages or use 1,3,5-8.
  3. Choose position, angle, size and opacity.
  4. Create the copy and inspect its beginning, middle and end for obscured information.

Compatibility and review

The font supports common letters and punctuation but no emoji. Existing marks are not removed. Limits are 500 pages, 18 to 72 points and 10% to 60% opacity.

Encrypted or damaged files may fail. Preserve the original, clearly name the copy and verify forms, annotations and signatures; the PDF is rewritten locally.