PDF Kaam
← All tools

Watermark PDF

Stamp a diagonal text watermark across every page.

This file never leaves your device

Add a text watermark to a PDF without uploading it

Watermarking is normally about marking a copy of a document you are handing to someone else — writing CONFIDENTIAL across a contract, or stamping an ID scan with the purpose it was shared for so it cannot be reused elsewhere. Marking an ID scan to limit its reuse and uploading that same scan to an unknown server are hard to do at once.

This tool draws your text diagonally across every page of the PDF inside your browser and returns the stamped file directly to you.

How to use it

  1. Open the watermark tool and select your PDF.
  2. Type the text you want stamped across the pages.
  3. Press Add Watermark. The text is drawn onto every page in your browser.
  4. Download the watermarked PDF.

Questions

Can the watermark be removed by someone else?
The text is drawn into the page content rather than added as an annotation, so it cannot be toggled off in a viewer. A determined person with the right software can still edit it out — a watermark deters casual reuse, it is not a security control.
Can I use an image or a logo as the watermark?
Not currently. This tool stamps text only.
Does PDF Kaam add its own watermark to my files?
No. The only watermark on your output is the text you typed. No tool on this site brands, stamps or adds a page to your document.
Are my files uploaded to a server?
No. Every tool on this site runs inside your browser tab using WebAssembly. Your file is read from your disk into the tab's memory, processed there, and written back out as a download. It is never sent over the network, so there is no server copy to leak, subpoena, or forget to delete.
Does the site send anything at all when I use a tool?
One thing, and only this: when a task finishes, the site records which tool was used, whether it worked, roughly how long it took, and which size band the input fell into. That is the entire list. No filename, no part of any file, no exact file size, no account, no cookie, and no identifier of any kind — there is deliberately no way to link two of these records to the same person. It exists so we can see which tools people actually use. Your file is still never transmitted, and the Content-Security-Policy header on this page still forbids the site from sending anything to any server but this one, which you can verify in the network tab of your browser. If your browser sends Do Not Track or Global Privacy Control, nothing is recorded at all.
Do I need to create an account?
No. There is no signup, no email, and no login on any tool. You can use every tool an unlimited number of times without identifying yourself.
Is there a file size limit or a daily limit?
There is no daily limit and no artificial size cap. The real ceiling is your device's memory: roughly 200-500MB per file on a desktop, and closer to 50-100MB on a low-end Android phone. Past that the browser tab can run out of memory.
Is the output watermarked?
No. Output files are clean. Nothing is stamped on them, and no page is added.
Does it work on a phone?
Yes. The tools run in any modern mobile browser, including Chrome on Android and Safari on iOS. Large files are slower on a phone than on a laptop because the processing happens on the device itself.
Does it work without an internet connection?
You need a connection to load the page the first time. Once the page has loaded, the actual PDF processing needs no network at all — you can turn off your Wi-Fi before pressing the button and the tool will still work.