Is Add watermark free?

Yes. Add watermark is free and works without an account, for files up to 25 MB and 150 pages. A free account raises that to 50 MB and 400 pages.

Are my files uploaded to a server?

No. Add watermark runs in your web browser, so the file is read on your own device and never sent to ConvertFile.

Can someone remove my watermark?

A watermark is drawn on top of the page. It discourages reuse, but someone with PDF editing software can remove it.

Does Add watermark work on Mac, Windows, Android and iPhone?

Yes. It runs in any modern web browser, with nothing to install. Very large files work best on a desktop or laptop, because in-browser tools use your device's memory.

Add watermark

Place text or an image across your pages.

Runs in your browser. Your file is never uploaded.

Add watermark in short

Add a PDF, type your watermark text (or choose a PNG or JPG image, such as a logo), then set the size, colour, opacity, angle and position: one of eight spots, centred, or repeated across the page. Click any page you want to leave out, and download. Text in any language works, because non-Latin text uses an embedded Unicode font. The watermark is drawn on top of the page, so it discourages copying but someone with a PDF editor can remove it.

How to use Add watermark

1Add a PDF.
2Type text or choose an image, then set position, size, opacity and angle.
3Download the watermarked file.

Good to know

A watermark is drawn on top of the page content. It discourages reuse but can be removed with editing software.
Page numbers mean physical positions in the file: page 1 is the first page, whatever number is printed on it.
This tool runs in your browser. Very large files depend on your device's memory.

What a watermark adds to a 12-page document

We stamped a 26.0 KB, 12-page text document with the default watermark (CONFIDENTIAL, 54 pt, 25% opacity, 45°) in three ways.

What a watermark adds to a 12-page document
Watermark	File size	Change
Original, no watermark	26.0 KB
CONFIDENTIAL, centred	30.4 KB	+16.7%
CONFIDENTIAL, repeated across the page	36.3 KB	+39.5%
The same word in Cyrillic, centred	34.3 KB	+31.9% (includes the embedded font)

A text watermark is stored as real text, so search and copy pick it up along with the page. Measured on 1 November 2026 by running this page's code on sample documents we generated ourselves.

Limits

Without an account: files up to 25 MB and 150 pages. With a free account: 50 MB and 400 pages.
Image watermarks accept PNG and JPG. PNG keeps transparent backgrounds, which usually looks better for logos.
The same watermark goes on every selected page.

What happens to your file

Add watermark runs in this browser tab. Your PDF is read and rewritten on your own device and handed back as a download; it is never sent to ConvertFile. We record only that the tool was used (its name and whether it finished), never file names, sizes or contents. Closing the tab discards everything.

If something goes wrong

Can I make the watermark impossible to remove?: No tool can. A watermark is an extra layer on the page and PDF editors can delete it. For something harder to strip, convert the watermarked file with PDF to image and back with Image to PDF, which flattens everything into pictures but also makes the text unselectable.
The watermark hides the text underneath: Lower the opacity (25% is the default) or the text size, or pick a lighter colour.
My logo has a white box around it: The image has a solid background. Use a PNG with a transparent background instead of a JPG.

Guides

How to flatten a PDF, and when you should
Flattening locks form answers, comments and stamps into the page so nobody can change them. What it does, when to do it, the steps, and what it can't undo.

Add watermark: common questions

Is Add watermark free?: Yes. Add watermark is free and works without an account, for files up to 25 MB and 150 pages. A free account raises that to 50 MB and 400 pages.
Are my files uploaded to a server?: No. Add watermark runs in your web browser, so the file is read on your own device and never sent to ConvertFile.
Can someone remove my watermark?: A watermark is drawn on top of the page. It discourages reuse, but someone with PDF editing software can remove it.
Does Add watermark work on Mac, Windows, Android and iPhone?: Yes. It runs in any modern web browser, with nothing to install. Very large files work best on a desktop or laptop, because in-browser tools use your device's memory.