Watermark PDF
Stamp a text watermark such as CONFIDENTIAL or DRAFT across every page of a PDF, once per page or tiled.
Mark documents as CONFIDENTIAL, DRAFT, or with your company name before sharing them. Choose a single diagonal stamp or a tiled pattern, and control the size and opacity. The watermark is drawn into the file itself, in your browser.
Your file never leaves your browser — the watermark is stamped on your device. The watermark is drawn on top of the page content and becomes part of the file.
How to use this calculator
- Choose the PDF to watermark.
- Type the watermark text, e.g. CONFIDENTIAL.
- Choose one stamp per page or a tiled layout, then set opacity and size.
- Click Add Watermark and save the stamped file.
The formula
In tiled mode the stamp repeats on a grid spaced 260 pt horizontally and 220 pt vertically, rotated −35 degrees — on a 612 x 792 pt Letter page that is 3 columns by 4 rows = 12 stamps.
Worked example
A Letter page in centered mode gets one diagonal stamp at the exact center of the page (x = 306, y = 396). In tiled mode the same page gets 12 stamps.
Frequently Asked Questions
Can the watermark be removed later?
The text is drawn onto each page as real page content, not as a removable annotation layer, so casual removal is difficult. Determined editing with full PDF tools can still alter any PDF, so treat a watermark as a deterrent and a label — not encryption.
What is the difference between centered and tiled?
Centered places one large diagonal stamp in the middle of each page — best for DRAFT or CONFIDENTIAL on normal documents. Tiled repeats the text across the whole page in a grid (12 stamps on a Letter page with default spacing), which is harder to crop out of images or scans.
What opacity should I use?
Around 20-35% keeps the watermark clearly visible without fighting the document text. Lower values (10-15%) are a subtle ownership mark; higher values suit 'DO NOT COPY' style notices on samples.
Does the watermark appear on every page?
Yes, every page of the document is stamped with the same text, size, and opacity. Each page is measured individually, so mixed page sizes in one file are handled correctly.