A watermark tells anyone who sees a document what it is and where it came from. "DRAFT" stops an unfinished version being mistaken for the final one. "CONFIDENTIAL" reminds people not to forward it. And a line like "Copy for ABC Lettings only, 12/03/2026" across an ID scan makes it far less useful if it ever ends up in the wrong hands. This tool adds text watermarks to every page of a PDF, right in your browser.
Settings that matter
Type your text, then adjust the size, color and opacity. Around 20 to 30% opacity keeps the page readable underneath while still being obvious. Choose Diagonal for the classic look across the middle of the page, or Horizontal for something quieter. Repeat across the page tiles the text over the whole sheet, which is much harder to crop out. The quick buttons give you the common words in one click: CONFIDENTIAL, DRAFT, COPY and SAMPLE.
A genuinely good habit for ID copies
Letting agents, employers, banks and landlords ask for a copy of your passport or driving licence is routine, and it's also how identity documents end up being misused. Adding a watermark that says who the copy is for and the date doesn't stop them using it for its real purpose, but it makes the copy far harder to reuse for anything else. It takes thirty seconds here. Choose the "Copy for … only" button, replace the placeholder with the recipient's name, set a smaller size so the text fits, tick the repeat option, and save.
Text, not a picture
The watermark is added to each page as real text, not a flattened image, so it's crisp at any zoom and doesn't make the file much bigger. Because it's text, it's also placed correctly on pages that are rotated or have unusual sizes. If you need it to be impossible to separate from the page content, finish with Flatten PDF, which merges everything into one layer or converts the page to a picture.
When to use which words
- DRAFT on anything still being reviewed, so no one signs or pays against a version that may change.
- CONFIDENTIAL on internal reports, salary data or legal letters.
- COPY on scans of originals, so nobody mistakes them for the real document.
- SAMPLE on preview pages of something you sell, to discourage people from just using the preview.
- Recipient and date on anything personal you send to a third party.
What a watermark can and can't do
Be realistic: a watermark discourages casual misuse, but a determined person with editing software can remove one, especially a single large word placed in the middle. A tiled watermark is harder to remove than a single one, and one that includes the recipient's name makes leaks traceable. For documents where tampering is a serious risk, combine it with a flattened file, remove hidden information with the metadata editor, and, if you need to hide specific details, use Redact PDF, which removes them permanently instead of covering them.
Building a finished document
A typical routine for a document going to a client: fix the page order with Organize PDF, add page numbers, add the watermark, compress the file for email, and send. For a signed copy, sign the PDF before you watermark it, so the watermark sits over the signature and shows the whole page is covered.
The tool runs in your browser and the document never leaves your device. That's useful when the file you're marking is itself sensitive. Protected files need to be unlocked in your reader first, and the watermark applies to every page, so if you only want it on some pages, split those out, mark them, and merge them back.
A worked example
You've written a proposal for a client and want to show it to two stakeholders before it's final. Add "DRAFT, not for distribution" in a mid-grey at 25% opacity, diagonally across every page, then save it as a separate file named "proposal-v2-DRAFT.pdf". Everyone who sees it knows what it is, nobody mistakes it for the final version, and when the proposal is approved, you start again from your clean original and export the final file without any mark. The whole process takes about a minute.
Choosing colors and sizes that actually work
Red catches the eye and suits "CONFIDENTIAL" or "DRAFT", but it can be distracting over dense text, so lower the opacity. Mid-grey is more discreet and good for "COPY". Size matters: a large word across the page is clearly visible, while a smaller repeated phrase is harder to remove. For text-heavy pages, try 15–20% opacity so the underlying words remain easy to read. Always scroll through the first few pages after saving to make sure the watermark isn't hiding anything important, such as a number in a table.
Whatever words you choose, review one page before you send the whole document, and keep your unmarked original in a safe place so you can produce a clean copy when needed.