RunToolRunPDF Watermark
Add watermarks to PDF files.
How to Add a Watermark to a PDF
Select a PDF
Click the upload area or drop the document you want to protect.
Enter your watermark text
Type any text — "CONFIDENTIAL", "DRAFT", your company name — and it's stamped diagonally across every page.
Download the watermarked PDF
Save a new file with the watermark permanently embedded in each page.
A watermark is a visual mark, not protection
The watermark is drawn as text or an image onto each page, over or under the existing content. It is a normal PDF object, which means anyone with a PDF editor can select and delete it, and anyone who converts the pages to images can crop or paint it out.
This is worth saying plainly because watermarks are often applied in the belief that they secure a document. They do not. They deter casual misuse and make provenance obvious at a glance — that is their real and quite useful job.
What it is actually good for
Marking status is the most valuable use: DRAFT, CONFIDENTIAL, NOT FOR DISTRIBUTION, or a client name across a proposal. A reader who opens a printed page months later can tell instantly what they are holding, which prevents a draft being treated as final.
It also discourages casual reuse of sample work and portfolio pieces, and it makes an accidental forward more visible. None of that requires the mark to be unremovable — it requires it to be seen.
Designing one that works
The tension is between visibility and readability. A mark dark enough to be unmissable makes the text underneath hard to read; one faint enough to ignore does not do its job. Diagonal placement across the page centre at low opacity is the usual compromise, because it touches every part of the page while leaving lines legible.
Check it on the page with the most content and on the page with the least. A watermark that reads perfectly over a dense table can be invisible over a mostly empty page, and vice versa.
Above or below the content
Placed above, the mark is unmistakable but sits on top of text. Placed below, the page stays cleaner but the watermark can disappear under images and filled tables — and vanishes entirely under a full-page scan, since a scanned page is one opaque image covering everything beneath it.
For scanned documents, therefore, only an overlay works. That is a common surprise: a watermark applied to a scanned contract appears to do nothing until you realise it is hidden behind the scan.
If you need real restriction
Genuine control over a document requires encryption with a password, permissions set at the file level, or a rights-management system — not a mark on the page. Even those have limits: anyone who can read a document can photograph the screen.
The watermarking runs in your browser and nothing is uploaded, which matters given that the documents people watermark are usually the confidential ones. As with any modification, an existing digital signature will be invalidated.