Watermark PDF
Center a diagonal text watermark on every PDF page and inspect the actual output page by page.
- 1Add input
- 2Adjust settings
- 3Get your result
Tool input and files are processed in this browser without being uploaded.
Before you start
Add one diagonal label to every page of a local PDF. The text is centered within each visible page and reduced when needed to avoid clipping, including on landscape and rotated pages.
How to use this tool
- Choose one local PDF, then enter a short ASCII watermark label in the visible controls.
- Set the requested font size and opacity; generate the PDF. The label is centered and can shrink on narrower pages.
- Use the output page selector to inspect every page, then download the watermarked PDF.
Supported inputs and limits
Printable ASCII characters only, 1–80 characters. Requested size 6–150 pt (whole points) and opacity 0.05–1 (up to two decimals). Long labels shrink to fit; text that cannot fit at 6 pt is rejected.
One unencrypted PDF up to 30 MiB and 300 pages. A watermark can be edited or removed and does not protect the document; changing a signed PDF may invalidate its signature.
The PDF is processed locally in this browser. Review every output page before downloading.
Worked example
Example input
three-pages.pdf
Example options
{"watermark":"DRAFT","size":48,"opacity":0.2}Example output
result.pdf (application/pdf)
When something does not work
If the label is rejected, use 1–80 printable ASCII characters or shorten it to fit at 6 pt. Correct the size or opacity, then generate and inspect the PDF again.
Frequently asked questions
Will a long watermark be cut off?
The label is centered and reduced to fit each visible page. Pages with different sizes can use different watermark sizes. The result reports how many pages needed smaller text. If it cannot fit at 6 pt, shorten the label.
Does a watermark protect my PDF?
No. A PDF editor can modify or remove it. This tool does not encrypt the file or restrict access, and changing a signed PDF may invalidate its signature.
Is my PDF uploaded?
No. Processing and page previews stay in this browser. Save the result before closing or refreshing the tab.