ALLYX ONE
100% browser-based · zero uploads

PDF Watermark

Add a custom text watermark to any PDF in seconds — free, no account required, and your file never leaves your device. Choose your text, adjust opacity, rotation and colour, then download the result instantly.

Drop your PDF here, or browse

PDF files up to 100 MB

How It Works

1

Pick your PDF

Drop a PDF onto the page or click to choose it from your device. Files up to 100 MB are supported.

2

Customise your watermark

Set the text, size, opacity, rotation and colour. Choose where it sits on the page — centre, corners, or anywhere in between.

3

We apply it here

Your PDF is processed entirely on your device — not sent anywhere. The watermark is drawn directly onto each page, keeping all existing text selectable.

4

Download your result

Download the watermarked PDF straight to your device, ready to share or distribute.

How to Add a Watermark to a PDF Online

  1. Drop your PDF onto the upload area or click to select it from your device.
  2. Enter your watermark text — for example: CONFIDENTIAL, DRAFT, or your company name.
  3. Adjust font size, opacity, rotation and colour using the sliders and colour picker.
  4. Choose where the watermark appears: centre, top-left, top-right, bottom-left, or bottom-right.
  5. Toggle Apply to all pages on or off depending on your preference.
  6. Click Apply Watermark and your browser processes the file instantly.
  7. Click Download watermarked PDF to save the result.

Features

  • Your file stays private: Watermarking happens entirely in your browser — nothing is uploaded or stored.
  • No account required: Open the page and start adding watermarks straight away.
  • Full control: Adjust text, font size (12–120pt), opacity (5–100%), rotation (0–360°), colour, and position — five placement options available.
  • Text stays selectable: The watermark is layered directly using pdf-lib — original page content is never re-rendered as an image.
  • All pages or first page: Stamp every page or just the cover in one click.
  • Up to 100 MB: Handles large multi-page documents.

Frequently Asked Questions

Is my PDF uploaded to your servers?

No. Your file never leaves your device. Everything runs in your browser using JavaScript — nothing is sent to or stored on any server.

Is this free to use?

Yes, completely free. No account required, no hidden charges, and the tool itself adds no visible branding to your PDF.

Can I control the look of the watermark?

Yes. You can set the watermark text, font size (12–120pt), opacity (5–100%), rotation (0–360°), colour, and placement position. Five position options are available: centre, top-left, top-right, bottom-left, and bottom-right.

Will existing text in my PDF still be selectable?

Yes. The watermark is drawn directly onto the page using pdf-lib's page.drawText(), which adds a new layer without re-encoding the existing page content. All original text, links and formatting remain intact and selectable.

How large a PDF can I watermark?

Up to 100 MB per file. Processing speed depends on your device since everything runs locally — no server round-trip time.

Which browsers are supported?

The tool works in all modern browsers — Chrome, Firefox, Edge, and Safari. No plugins or extra software needed.