Stamp a custom text watermark on every page of your PDF in seconds — privately in your browser.
Adding a watermark to a PDF is one of the most effective ways to protect your intellectual property, mark documents as confidential, or brand your deliverables. PDF Toolkit's free watermark tool lets you stamp any custom text — such as CONFIDENTIAL, DRAFT, SAMPLE, or your company name — diagonally across every page of your PDF. The watermark is applied at a standard 45-degree angle with a professional opacity level that makes it clearly visible without obscuring the document content. Since all processing happens locally in your browser using WebAssembly, your sensitive documents never leave your device. The watermark is permanently embedded into the page content — it appears in print and in any PDF viewer, and cannot be easily removed by standard tools. For maximum document security, combine this with our Protect PDF tool.
Click "Select a PDF file" and upload the PDF you want to watermark.
Enter your watermark text in the input field. Common examples: CONFIDENTIAL, DRAFT, SAMPLE, your company name.
Click "Apply Watermark and Download". Processing is instant and happens in your browser.
Your watermarked PDF is downloaded automatically. The original file is not modified.
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