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Add Watermark to PDF Online

Stamp custom diagonal or centered text watermarks across every page of your PDF document locally in your browser.

Choose a PDF file to watermark Processed locally on your device—ideal for confidential contracts and drafts.

Watermark Text

Placement & Angle

Opacity: 25%

Next step in your workflow:

Compress PDF →Merge PDF →Split PDF →Add Page Numbers →

Protect Drafts, Invoices & Legal PDFs with Custom Text Watermarks

Adding a visible watermark such as CONFIDENTIAL, DRAFT, SAMPLE, or your company name deters unauthorized copying and clarifies document status before you share files with clients, vendors, or students.

How to Watermark a PDF in 3 Steps

Select your PDF document in the upload box above.
Enter your custom stamp text, choose Diagonal Center, Horizontal Center, Top Header, or Bottom Footer placement, and set your preferred transparency (15%–30% keeps underlying text easy to read).
Click Apply Watermark & Download PDF to save your stamped document immediately.

Frequently Asked Questions

Does watermarking alter the original text of my PDF?

No. Your original text, links, and layout remain intact; the watermark is drawn as a semi-transparent overlay layer on each page.

Is my confidential PDF uploaded to any server?

Never. Watermarking runs 100% locally in your browser using pdf-lib.