Watermark PDF
Add a custom text watermark to every page of a PDF. Choose diagonal or centered placement, set opacity and font size. Runs entirely in your browser.
Options
Cómo funciona
Upload your PDF file
Enter your watermark text and adjust position, opacity, and size
Download the watermarked PDF — applied to every page
Preguntas frecuentes
Can I use any text as the watermark?
Yes — type any text such as CONFIDENTIAL, DRAFT, your company name, or any custom label.
Is the watermark permanent?
Yes. The watermark is embedded into the PDF pages. It cannot be removed without specialized software.
Is my PDF uploaded to a server?
No. Watermarking is done entirely in your browser using pdf-lib. Your file never leaves your device.
Can I add a watermark on my phone?
Yes. OneConvertly works in any modern mobile browser including Safari on iPhone and Chrome on Android. No app needed.
Is there a file size or page limit?
Files up to 200MB are supported with no page limit. The watermark is applied to every page automatically.
Can I add an image watermark instead of text?
Currently only text watermarks are supported. Image/logo watermark support is planned for a future update.
Is this tool free?
Yes, completely free. No signup, no daily limits, and no extra watermarks added by OneConvertly.