How to Add a Watermark or Stamp to a PDF (Free, Online)
A watermark is text stamped across the pages of a document. It tells the reader something at a glance: "CONFIDENTIAL" on a contract, "DRAFT" on an unfinished report, a company name on a quote you are sending out, or "COPY" on a document that is not the original.
How to add a watermark to a PDF
- Open the Add watermark tool and add your PDF.
- Type the watermark text, for example CONFIDENTIAL, DRAFT, SAMPLE or your company name (up to 100 characters).
- Choose the placement: diagonal (across the page at 45 degrees) or centred.
- Set the opacity. Lower means fainter. The default is 30%.
- Optionally set the font size. Leave it empty and the size fits the page automatically.
- Press the Add watermark button and download the stamped PDF.
Diagonal or centred?
| Placement | Looks like | Good for |
|---|---|---|
| Diagonal | Large text running across the page at 45 degrees | CONFIDENTIAL, DRAFT, SAMPLE: the classic look |
| Centred | Horizontal text in the middle of the page | A company name or a short label |
Choosing the opacity
| Opacity | Effect |
|---|---|
| 10 to 20% | Very faint, the page stays easy to read |
| 30% (default) | Clearly visible and still readable |
| 50% or more | Strong mark, makes text underneath harder to read |
If people need to read the document, stay at or below 30%. For a "DO NOT COPY" warning that must be seen, go a little higher.
Common uses
- Draft documents: mark a report or proposal as DRAFT so nobody mistakes it for the final version.
- Confidential files: stamp CONFIDENTIAL on contracts, financial reports and internal documents.
- Samples and previews: put SAMPLE on a document you share before a sale.
- Copies: mark a scan or duplicate as COPY.
- Branding: add your business name to a quote or price list.
What a watermark does not do
A watermark is a visible mark only. It does not stop anyone from reading, copying or printing the document, and it can be covered or cropped by someone determined to. If you need real protection:
- Stop people opening the file with Protect PDF (read our guide to password-protecting a PDF).
- Remove sensitive words for good with Redact PDF.
Tips
- Check one or two pages of the result, especially pages with images or tables.
- If you also need page numbers, add them with Add page numbers (see our page numbers guide).
- If the file is large, run Compress PDF afterwards.
Is my file safe?
Your file is encrypted in transit and at rest and deleted automatically, by default within 2 hours. See the privacy page.
Frequently asked questions
Can I add a text stamp like CONFIDENTIAL or DRAFT?
Yes. Type any text up to 100 characters and it is stamped on every page.
Can I control how faint the watermark is?
Yes. Set the opacity between 5% and 100%. The default of 30% keeps the page readable.
Where does the watermark go?
You can place it diagonally across the page at 45 degrees, or horizontally in the centre.
Does a watermark protect my PDF?
No. It is a visible mark, not a security feature. To stop opening, use Protect PDF, and to remove words for good, use Redact PDF.