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Watermark PDF

Stamp text like CONFIDENTIAL or DRAFT across every page with adjustable opacity and position.

Select PDF files
or drop files here
Limited by device memory · Files stay on your device
🔒 100% on-device·No signup·Free forever

Watermark PDF online, free and private

A watermark is the quickest way to label a PDF for what it is — ‘Draft’, ‘Confidential’, ‘Sample’, or your company name — so the status travels with the document no matter who opens or reprints it. This tool stamps a text watermark across every page at once, with adjustable opacity and a 3×3 position grid, and a live preview so you can see exactly how it lands before you commit.

Everything happens inside your browser. Your PDF is read into memory, the watermark is drawn onto each page locally with pdf-lib, and the finished file is handed straight back to you. Nothing is uploaded to a server, so contracts, drafts, and sensitive reports never leave your device.

How to watermark pdf in your browser

  1. 1

    Add your PDF

    Click ‘Select PDF file’ or drop it onto the page. The document loads instantly and appears in the live preview so you can see the pages you are about to mark.

  2. 2

    Type your watermark text

    Enter the words you want stamped — ‘CONFIDENTIAL’, ‘DRAFT’, a date, or your name. The preview updates as you type so there are no surprises.

  3. 3

    Set opacity and position

    Drag the opacity slider to make the text bold or a faint background tint, then pick a spot on the 3×3 grid — corner, edge, or dead centre — to place the watermark on each page.

  4. 4

    Apply and download

    Press the watermark button and the text is drawn onto every page in your browser. The stamped PDF is ready to download in a couple of seconds.

Why use PDFToolz for this

Your document stays private

The watermark is applied with client-side JavaScript, so your PDF is never transmitted. There is no server copy to cache or leak — a genuine advantage when the file is a confidential draft, a legal document, or an internal report.

See it before you commit

The live preview shows the real watermark at your chosen opacity and grid position, on your actual pages. You can fine-tune the text and placement until it reads clearly without hiding the content underneath.

Every page, in one pass

The watermark is stamped consistently across all pages of the document, so a hundred-page report gets the same label as a one-page memo. Text stays selectable and the original pages are left otherwise untouched.

Free, unlimited, and offline

There is no account, watermark-on-your-watermark, or page cap. Because the work runs locally, the tool keeps working even after you disconnect from the internet once the page has loaded.

Frequently asked questions

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