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PDF Watermark

Stamp a text watermark on every page of a PDF. Diagonal or banner placement, with opacity, size, and color control.

PDF
Drop a PDF here or click to browse
or paste from clipboard (Ctrl+V) · PDF
Files stay in your browser. Nothing is uploaded.

How to add a watermark to a PDF online

  1. Add your PDF

    Drop the PDF on the tool, click to browse, or paste it from your clipboard. The file stays in your browser.

  2. Type the watermark text

    Enter the text to stamp, such as DRAFT or CONFIDENTIAL. It lands on every page as soon as you type.

  3. Style the stamp

    Pick diagonal or a top or bottom banner, then set the size, opacity, and color. Every change re-stamps the PDF instantly.

  4. Download the PDF

    Click Download PDF to save the watermarked document. The filename gets a -watermarked suffix.

Why use this tool

Diagonal or banner placement

The default stamp runs at 45 degrees across the center of each page. Top and bottom options draw a horizontal banner instead.

Opacity, size, and color control

Fade the stamp from 10 to 60 percent, pick one of three sizes, and choose grey, red, or blue.

Every page, one pass

The text is stamped on every page of the document in bold Helvetica. No page-by-page setup.

Instant re-stamping

Each settings change re-stamps the PDF straight away, so the download always matches what you picked.

Long text fits automatically

Text wider than the page is scaled down to fit, and the tool notes when that happened.

Runs entirely on your device

The PDF is loaded, stamped, and saved in your browser. No upload, no signup.

About this tool

This tool stamps a line of text across every page of a PDF, directly in your browser. Drop a document, type the text, and the stamp lands on each page as you type. The default style is diagonal: large bold Helvetica at 45 degrees across the center of the page. Top and bottom draw a horizontal banner instead. Opacity runs from 10 to 60 percent, three sizes cover most documents, and the color is grey, red, or blue. Text too long for the page is scaled down to fit, with a note when that happens.

The usual jobs are stamping DRAFT on work that is still moving, CONFIDENTIAL on documents that should not travel, and a client name on proofs before they go out for review. Be clear about what a watermark does: it signals status, it does not encrypt anything. A determined reader with the right software can remove an overlay, so treat the stamp as a label, not a lock. Because the stamp is drawn on top of the page as an overlay, the original text underneath stays selectable and searchable.

The tool takes one file at a time on purpose. Watermarking is a per-document decision, and the settings that suit a contract rarely suit a slide deck. Everything runs on your device, so a document marked CONFIDENTIAL never touches a server on its way to being stamped. To stamp a photo or graphic instead, watermark an image does the same job for JPEG, PNG, and WebP. If the document also needs numbering, add page numbers to PDF works the same way, and a file still in pieces can be assembled first with merge PDF.

Frequently asked questions

What watermark styles are available?
Three placements: a diagonal stamp at 45 degrees across the center of the page, which is the default, or a horizontal banner at the top or bottom. Each comes in three sizes, three colors (grey, red, or blue), and any opacity from 10 to 60 percent.
Can the watermark be removed?
By a determined person, yes. The stamp is an overlay drawn on top of the page, and dedicated software can strip overlays out. A watermark signals the status of a document; it does not protect the contents. If a file genuinely must not leak, use encryption or access control as well.
What opacity should I use?
The default 25 percent reads clearly without getting in the way of the text underneath. Push it to 40 or higher when the stamp must be unmissable, such as DRAFT on a proof, and drop it to 10 or 15 for a quiet background mark.
Does the watermark cover the text underneath?
The stamp sits over the page, but the original text stays selectable and searchable because nothing underneath is changed. At the default opacity the page remains comfortably readable.
Can I watermark several PDFs at once?
No, the tool takes one file at a time on purpose. A watermark is a per-document decision. Use Replace to load the next file, and your text and style settings stay as they are.
Is my PDF uploaded anywhere?
No. The document is loaded, stamped, and saved entirely in your browser. It never leaves your device, which is the point when the file is confidential enough to need a stamp.

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