Add a watermark to a PDF
Stamp DRAFT, CONFIDENTIAL, a client name or any other text across every page of a document. Choose diagonal or tiled, set the size, opacity, colour and rotation, and check it on a live preview first. The watermark is drawn in your browser and baked into the PDF you download — the file itself is never uploaded.
How to add a watermark to a PDF
Load the PDF
Drop your document in and the first page appears as a preview.
Write and style the watermark
Type your text, then set the opacity, size, rotation and colour. Choose a single diagonal stamp or a tiled pattern across the whole page.
Stamp every page
Press Apply. The watermark is drawn onto each page and the finished PDF downloads.
What Add Watermark to PDF can do
Diagonal or tiled
One bold stamp across the page, or a repeating pattern that's hard to crop out.
Opacity and colour control
Keep it legible without burying the text underneath it.
Live preview
Adjust and re-check on a real page before writing the file.
Applies to every page
One pass stamps the whole document, however long it is.
Add Watermark to PDF — frequently asked questions
Can the watermark be removed again?
It's drawn into the page content, so it can't be toggled off — but a determined editor could still delete the drawing. If the point is that nobody can change it, run the stamped file through Flatten PDF in rasterise mode.
Can I add an image or logo as a watermark?
This tool stamps text. For a logo, open the file in the PDF Editor and place the image where you want it.
Does the watermark cover the text underneath?
Not if you keep the opacity below about 30%. The preview shows exactly how it will read before you commit.
Do my PDFs get uploaded to a server?
No. Every tool on Notoo Tools runs as JavaScript and WebAssembly inside your browser tab. There is no server that receives your files — you can disconnect from the network after the page loads and the tool keeps working.
Do I need an account or a subscription?
Neither. There's no sign-up, no email, no free-tier limit and no watermark. Bookmark the tool and it opens straight into the work.