Watermark PDF
Write text like CONFIDENTIAL or COPY across every page.
Everything runs right here in your browser, on your own device.
Drop your PDFs here
or choose files from your device
Choose files to get started.
Choose. Change. Download.
Drop them in the box or choose them from your device.
Set the options and press the tool’s button.
Check it and save it. Your originals stay unchanged.
Common questions
Step-by-step instructions
Type the text, then choose diagonal or straight, the opacity and the colour. It’s centred on every page, or only on the pages you list. The text sits on top of the content, and the document isn’t turned into images. Add several PDFs to process them one after another with the same settings. Results are grouped by source file and can also be downloaded in one global ZIP.
When to use it
Use it to mark copies you send to others, drafts that aren’t final yet, or internal documents. A watermark with the recipient’s name, such as “Copy for the accountant”, helps you tell where a document came from if it’s forwarded.
Before you start
It’s a visible mark, not protection: anyone with a PDF editor can remove it. If you want the PDF not to open without a password, use Protect PDF. It supports the usual Latin-alphabet characters. Any change invalidates digital signatures.
Are my PDFs uploaded anywhere?
No. Processing is local and we do not store files or filenames on a server. GitHub Pages receives normal page requests and may log connection information. This version has no analytics, advertising or trackers.
Is it free? Is there a daily limit?
Yes. There is no daily limit, per-document quota or paid plan. Run successive batches as needed. Safety limits are 150 MB per file, 500 pages for rendering and 25 million pixels per page. Available memory may impose lower limits.
Does it work on a phone?
Yes, in modern browsers. A computer often has more memory for large documents. Keep the tab open during processing and check the PDF before sending it.