Add Watermark to PDF

PDF FLINT adds customizable text watermarks to your PDF documents, letting you mark pages as Draft, Confidential, or branded with your company name. You control the font, size, color, opacity, rotation angle, and position of the watermark, and it is applied consistently across every page in a single operation.

The watermarking engine renders your text onto each page of the PDF as a transparent overlay using client-side processing. You see a live preview of the watermark appearance before applying it, so you can fine-tune opacity and placement until it looks right. The watermark is embedded into the PDF structure, meaning it persists when the file is shared, printed, or viewed in any PDF reader. The added data is minimal, so file size barely increases. The entire process runs in your browser — your document and watermark text are never sent to a server.

Watermarking serves two main purposes: intellectual property protection and document status labeling. Photographers, designers, and authors use watermarks to deter unauthorized redistribution of proofs and drafts. Businesses use status labels like "Draft," "Confidential," or "For Internal Use Only" to control how documents are handled. Legal and compliance teams mark sensitive materials to establish a clear audit trail. PDF FLINT handles all of these scenarios without requiring expensive desktop software.

Your documents remain fully private since nothing leaves your browser during processing. There are no page limits, no watermarks-on-your-watermark, no daily usage caps, and no account required. Open PDF FLINT, customize your watermark, and download the protected document.