Watermark
Stamp every page with a custom text watermark. Control opacity, rotation, and color.
100% in your browser — files never leave your device
When to use a PDF watermark
Watermarks communicate document status at a glance — reviewers know a draft is not final, recipients know a copy is for reference only, and distributed files are clearly marked with ownership information. A diagonal "CONFIDENTIAL" stamp across every page is a standard part of legal and financial document workflows.
This tool lets you set any text, tune the opacity so the watermark is visible without obscuring the content, and adjust the angle. The result is written directly into the PDF page content, so the stamp appears correctly in every viewer and when the document is printed.
Because everything runs in your browser, sensitive documents — contracts, financial statements, HR files — never leave your device during the watermarking process.
Frequently asked questions
Are my files uploaded to add a watermark?
No. The watermark is applied entirely in your browser using pdf-lib. Your PDF never leaves your device — no upload, no account, no data retention.
Is the watermark permanent?
The watermark is drawn as content on each page, making it part of the PDF output. It is not a metadata tag. A determined recipient with a PDF editor could remove it, but it cannot be hidden or toggled off by opening the file normally.
Can I control how visible the watermark is?
Yes. You can adjust the opacity (5% to 50%), font size (12pt to 120pt), color, and rotation angle. The defaults — "CONFIDENTIAL" at 15% opacity, -45 degrees — are a common choice for document review workflows.
What text can I use as a watermark?
Any text string. Common choices are CONFIDENTIAL, DRAFT, DO NOT COPY, or a company name. The text is rendered on every page of the document.
Will the watermark cover the readable content?
At the default 15% opacity the watermark is clearly visible but does not obscure the underlying text. Increasing opacity makes it more prominent; the content remains readable at any setting within the provided range.