Add Watermark to PDF

About this tool

The UnblockPDF Watermark tool adds text or image watermarks to PDF documents, providing a visible layer of protection and identification for your files. The entire watermarking process runs inside your browser, which means your documents and any branding assets you use remain private and are never uploaded to an external server. For text watermarks, you can type any custom message such as 'Confidential,' 'Draft,' 'Sample,' or your company name. The tool provides full control over the text appearance including font family, font size, color, opacity level, and rotation angle. You can position the watermark at the center of the page, along the diagonal, or at any of the standard positions including top-left, top-center, top-right, bottom-left, bottom-center, and bottom-right. For image watermarks, you can upload a logo, stamp, or any graphic file in JPEG, PNG, or SVG format. The image watermark supports the same positioning and opacity controls as text watermarks, allowing you to create a subtle branding overlay or a prominent identification stamp. The image is scaled proportionally to fit within the page while maintaining its aspect ratio. By default, the watermark is applied to every page of the document. You can restrict it to specific pages by entering page numbers or ranges, which is useful when you want to watermark only the cover page or selected sections. The watermark is rendered as an overlay on the existing content, and you can choose whether it appears in front of or behind the page content. Common use cases include marking documents as confidential before sharing with external reviewers, adding draft stamps to documents under review, branding company reports with a corporate logo, applying sample watermarks to protect digital products from unauthorized use, and adding ownership marks to creative portfolios. The watermarked output can be downloaded immediately or further processed with other UnblockPDF tools. The tool supports files up to 50 MB for anonymous users and 100 MB for registered accounts, and works across all modern browsers on any device.

Common use cases

Tips for best results

• Set the watermark opacity between 20 and 40 percent for a professional look that does not obscure the underlying content.
• Use the diagonal center position for text watermarks like Confidential to ensure maximum visibility across the entire page.
• After watermarking, use the Flatten tool to permanently embed the watermark so it cannot be removed by other PDF editors.
• For brand consistency, upload your company logo as a PNG with a transparent background to blend naturally with the document content.