How Watermark PDF works
This tool draws a text watermark onto every page of a PDF — the same technique used to mark documents DRAFT, CONFIDENTIAL or SAMPLE before they're shared. You control the wording, colour, size, rotation angle and opacity, and the mark is drawn directly into the page content in your browser, so the source file never leaves your device.
How to get your result
- 1
Upload the PDF you want to watermark.
- 2
Type the watermark text — CONFIDENTIAL and DRAFT are common choices, but any short phrase works.
- 3
Adjust opacity, font size, rotation and colour until the mark looks right.
- 4
Download the watermarked PDF.
Common uses
Marking a document as a draft before review
Stamp DRAFT diagonally across a proposal or report so reviewers can't mistake it for the final version.
Protecting shared samples from misuse
Add a SAMPLE or your company name across pages before sending a preview PDF to a client or prospect.
Marking confidential internal documents
Stamp CONFIDENTIAL across a PDF before it's circulated internally, making the sensitivity level visible at a glance.
Why the watermark can't be removed with an 'unlock' tool
This watermark is not a password, a permission flag or a removable layer — it's ordinary page content, drawn with the same drawing operations a PDF library uses for any text. That means it displays identically in every PDF reader and survives printing, but it also means the original, unmarked file needs to be kept separately if you'll ever need a clean copy.
Choosing opacity, size and angle
A low opacity (15-30%) keeps the underlying text fully legible while still being unmistakably present, which is usually right for a document meant to be read as well as marked. A 45° rotation across the centre of the page is the conventional angle because it stays clear of a page's normal top-to-bottom text flow and margins, wherever they happen to fall.
Practical notes
- Keep the original file — this tool draws the watermark permanently into a copy, it doesn't produce a removable overlay.
- For a subtle mark on business documents, try 15-20% opacity rather than the 25% default.
- Short phrases (CONFIDENTIAL, DRAFT, SAMPLE) read clearly at large sizes; longer phrases need a smaller font to fit within the page width.