Watermark PDF
Add a diagonal text watermark like DRAFT or CONFIDENTIAL to every page.
Files are processed on your device and never uploaded.
Export
Watermark PDF in 4 steps
- Open the PDF.
- Type the watermark text.
- Adjust the size, colour, opacity and angle.
- Export and save the watermarked PDF.
Questions and limits
No. PDF Studio has no upload server. Your files are opened, changed and saved inside this browser tab by JavaScript and WebAssembly running on your device. You can check it yourself: open your browser's developer tools, watch the Network tab while you use the tool, and you will see that no request carries your file.
The watermark is drawn into each page's content, so it cannot simply be switched off in a reader. A determined person with PDF editing software can still remove it; a watermark discourages copying, it does not prevent it.
No. Changing a PDF writes a new file, and that invalidates any digital signature it had. Sign the document again after editing it.
There is no upload limit, because nothing is uploaded. The practical limit is your device's memory: desktop browsers handle files of several hundred megabytes. On phones and tablets we warn you above about 200 MB or 1,000 pages.
Yes, after the first visit. The app and the processing engines are stored in your browser's cache, so the core tools keep working without a connection once they have loaded once.