Add watermark to PDF files

1. This tool allows you to add watermarks to every page of a PDF file, including text or image watermarks.

2. After successfully adding a watermark, the first page of the PDF file will be displayed, allowing you to easily view the applied watermark style.

3. Note: When adding an image watermark, if you select the "Tile" mode, processing may take a significant amount of time; please be patient.

4. Note: The text watermark uses the "Noto Sans SC" font from the Google Fonts open-source library.

5. This tool processes PDF files entirely within your browser; please use it with confidence.