How to Add a Watermark to a PDF

Watermarking a PDF the right way

A document that leaves your hands can end up anywhere — forwarded, printed, posted. A watermark is the quiet label that says what the document is: DRAFT on a version that is not final, CONFIDENTIAL on a file that should not be shared, SAMPLE on a preview that is not the real thing. It does not stop anyone from reading the document, but it makes the status of the document visible on every page, to everyone who sees it.

This tool adds a diagonal text watermark to every page of your PDF. You type the text — DRAFT, CONFIDENTIAL, SAMPLE, or your name or company — and choose the color and the opacity. You can also add a date line, so the watermark says when the document was marked. The watermark is drawn onto the pages, so it travels with the file and cannot be switched off from a viewer. The text and images underneath do not change at all — the document is still searchable, and it prints as usual. You can watermark up to 20 files at once, 100 MB in total.

Opacity is the choice that matters most. For review on screen, a strong opacity is fine — the watermark should be obvious. For printing and close reading, choose a light opacity, so the text underneath stays comfortable to read. A watermark that hides the words it sits on has failed at its job: it should label the document, not make it unreadable. Check the result on screen and, if the document will be printed, print one page first and read it before you send the file out.

A few practical tips. Use one word that says what the document is for — DRAFT for a version under review, CONFIDENTIAL for a file that must not be forwarded, SAMPLE for a preview. A name or a company works when the point is ownership rather than status. Do not watermark a document you still need to edit heavily: the watermark is drawn onto the pages, and removing it later means starting from the original. Keep the unwatermarked file, and watermark a copy for distribution.

It also helps to know what a watermark does and does not do. It labels a document — it does not protect it. Anyone can read the text underneath, copy it, print it, or photograph it, and anyone with a PDF editor can remove a watermark if they try hard enough. A watermark is a label, not a lock. If the document must not be read at all, it needs a password, not a watermark — use the Protect PDF tool for that. And if the document must not be copied, there is no watermark in the world that stops a screenshot. Use the watermark for what it is good at: making the status of a document visible to everyone who sees it, on every page, without hiding the words underneath.

The choice of words matters, too. One word is usually enough: DRAFT, CONFIDENTIAL, SAMPLE, or a name. A long sentence across the page is harder to read and harder to ignore, and it covers more of the text below. A short word, in a light opacity, in a color that stands out from the page without shouting — grey on a white page, or a soft red — does the job and stays out of the way. And if the document will be read on a phone, check the watermark there: a mark that looks subtle on a large screen can look heavy on a small one, and a mark that is invisible on a phone is no mark at all.

Everything runs in your browser. Your PDF is never uploaded to a server, so a private document stays on your device. There is no account, no daily limit, and no watermark added by the tool itself — only the one you choose. Open the tool, drop your PDF, type your mark, and stamp every page.

How to use this tool

1. 1Drop a PDF onto the Watermark PDF page — up to 20 files, 100 MB in total.
2. 2Type the watermark text — DRAFT, CONFIDENTIAL, SAMPLE, or your name or company.
3. 3Choose a color and an opacity, and add a date line if you want one.
4. 4Press Add Watermark and download the file.
5. 5Open the result and check the watermark is readable but does not hide the text below.