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Watermark PDF. Privately.

Stamp CONFIDENTIAL, DRAFT or your name diagonally across every page. It all happens in your browser, so your file is never uploaded, and we don't add a watermark of our own. That's the part iLovePDF can't say.

100% in your browserNo upload, everNo signupUnlimited & free

Truly private

Files never leave your device

Instant

No upload/download round-trip

No limits

Any size, any page count

How it works

  1. 01

    Add your PDF

    Drop in a PDF, or click to browse. It stays on your device.

  2. 02

    Type your text

    Enter the watermark (e.g. CONFIDENTIAL or DRAFT) and pick how strong it should be.

  3. 03

    Download

    We stamp a diagonal watermark across every page in your browser. Nothing is uploaded.

More PDF tools: Merge · Split · Rotate · Compress · Page numbers · Organize · Crop · Sign · Redact · Add text · N-up · Protect · Unlock · Repair · PDF/A · OCR · To images · Extract images.

Check it yourself: your file is not uploaded

You do not have to take our word for it. Your browser can show you every request this page makes.

  1. Open the developer tools: press F12 in Chrome, Edge or Firefox on Windows, or Cmd+Option+I on a Mac, then choose the Network tab.
  2. Clear the list, then add your PDF and run Watermark PDF.
  3. Look at the requests that appear. An upload would be a request at least as large as your file; sort by size to find it.

What we saw when we did this on Merge PDF with two small PDFs: the browser fetched one script file of this site's own code (the PDF engine), and sent one message of about one kilobyte with page speed and engagement figures. No request carried either PDF, and the merged file was built and downloaded in the browser.

Common questions

Are my files uploaded?+

No. The watermark is added entirely in your browser with a local PDF engine. Your file never leaves your device. iLovePDF and most tools upload your PDF to their servers first.

Where does the watermark go?+

A single large watermark is placed diagonally across the centre of every page, at the strength you choose.

Can I change the opacity?+

Yes. Pick Light, Medium or Strong so the watermark is visible without hiding your content.

Is there a limit?+

No artificial caps. Free, unlimited, no signup or extra watermark of our own.

Does it keep quality?+

Yes. Your pages are untouched; we only overlay the watermark text.