ToolBrainy

Add Watermark to PDF Online Free

Stamp a text watermark across every page of your PDF, choose the color, opacity, size and layout, free and fully private in your browser.

Drag & drop your PDF here

or

Single PDF file · Processed in your browser

About this tool

Add Watermark stamps your own text, such as CONFIDENTIAL, DRAFT or your company name, across every page of a PDF. Choose the color, how transparent it is, the font size, rotate it to any angle with the angle slider, and pick a single centered mark or tile it across the page. Everything runs locally in your browser using pdf-lib, so your document is never uploaded and the original content stays exactly as it was.

Adding a watermark to a PDF is a fast way to protect and label your documents. Type the text you want, whether that is CONFIDENTIAL, DRAFT, SAMPLE or your company name, then fine-tune the color, opacity, size and angle until it looks right in the live preview. Choose a single centered stamp for a subtle mark or tile it across the whole page for stronger protection, and the same watermark is applied consistently to every page in one click.

Because the watermark is added in your browser with the open-source pdf-lib library, your file never leaves your device and nothing is stored on a server. That makes it a safe choice for contracts, proposals, invoices and other sensitive paperwork. It works on Windows, macOS, Linux, Android and iOS in any modern browser, so you can watermark a PDF online on your laptop or stamp one on your phone without installing an app or creating an account.

How to use

1
Upload a PDF

Drag & drop or choose a single PDF file.

2
Style your watermark

Set the text, color, opacity, size and layout.

3
Add & download

Stamp every page and save your PDF.

Why use it

Private by design

Watermarking happens locally, nothing uploaded.

Live preview

See exactly how it looks before saving.

Content preserved

Only the watermark is added, nothing else changes.

100% free

No signup, no limits and no forced badges.

Use cases

Confidential docs

Mark sensitive files as CONFIDENTIAL.

Drafts

Label work-in-progress as DRAFT.

Branding

Stamp your company name on every page.

Copyright

Discourage unauthorized reuse.

Samples

Mark previews as SAMPLE or SPECIMEN.

Approvals

Tag files as APPROVED or PAID.

Frequently asked questions

What text can I use as a watermark?

Any short text you like, for example CONFIDENTIAL, DRAFT, SAMPLE or your company name. It is applied to every page.

Can I control how it looks?

Yes. Set the color, opacity and font size, drag the angle slider to rotate it to any angle, and choose a single centered mark or tile it across the whole page.

Does it change the rest of my PDF?

No. Only the watermark is drawn on top, the existing content of every page is left untouched.

Is my PDF private?

Yes. Everything runs in your browser using pdf-lib, your file is never uploaded to a server.

Is the watermark tool really free?

Yes, it is completely free with no signup, no limits and no forced badges. You can watermark as many PDFs as you like.

Do I need to install any software?

No. The tool runs entirely in your web browser, so there is nothing to download or install. It works in any modern browser such as Chrome, Firefox, Edge and Safari.

Can I add a watermark on my phone?

Yes. The tool works in mobile browsers, so you can watermark a PDF on your phone or tablet the same way you would on a desktop.

Can I remove a watermark from a PDF?

This tool adds watermarks rather than removing them. Once you save, the watermark becomes part of the PDF, so keep your original file if you later need a clean copy.

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