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Add text or image watermarks to every page of a PDF online for free. Customize opacity, rotation, position, and color. 100% browser-based — your files never leave your device.
A PDF watermark tool embeds semi-transparent text or images on every page of a PDF document. Common uses include marking documents as "CONFIDENTIAL", "DRAFT", or branding pages with a company logo.
Drop a PDF here or click to browse
All processing happens in your browser.
Formula
opacity_alpha = user_opacity / 100user_opacity = Opacity percentage set by user (1–100)
opacity_alpha = Alpha channel value (0.01–1.0)
Worked Example
Centered text watermark on letter-size page
Did you know? PDF watermarks are embedded in the content stream, not as annotations, making them visible in print. The PDF spec supports 256 transparency levels for subtle watermarking.
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