All tools
Watermark PDF
Add a text watermark to a PDF locally in your browser.
Your files stay on your device. Processing happens locally in your browser — nothing is uploaded.
How it works
- Select your PDF — drag it into the drop zone or click to browse.
- Type the watermark text and pick its position and opacity.
- Choose all pages or just some, then apply the watermark.
- Download the watermarked PDF.
Why local processing?
Watermark PDF processes your file inside your browser, on your own device. Your document is not uploaded to our servers. The browser may download code needed to run the tool, but those requests do not contain your file.
Check it yourself: open your browser’s network tab while a file is being processed — your document never appears in any request.
Frequently asked questions
- Is my file sent to a server to be watermarked?
- No. The watermark is drawn onto each page inside your browser — the document is opened, stamped, and saved entirely on your device. Check the network tab while it runs: no file transfer appears.
- Is there a document size limit?
- Each file can be up to 200 MB. Processing happens in your browser and also depends on available memory. Large or complex files may be slow or exceed your device’s resources even below this limit.
- Can I watermark confidential, GDPR-relevant files?
- That is a typical use case: because there is no server-side processing at all, marking a contract “CONFIDENTIAL” does not require handing it to anyone.
- Can the watermark be removed later?
- The text is drawn into the page content, so casual removal is not trivial — but like any visible watermark it is not tamper-proof, and a determined editor could reconstruct the page. Treat it as labeling, not protection.
- What can I customize?
- The text itself, its position (diagonal across the page, or anchored to a corner or edge), its opacity, and which pages receive it.
Related tools
- Add Page Numbers — Stamp page numbers onto a PDF, in the position you choose.
- Edit PDF — Add text, shapes, highlights, lines, arrows, and cover boxes to a PDF locally in your browser. Experimental: this adds content on top of the PDF and does not directly edit existing text.