Add Watermark to PDF Online Free

Watermark PDF Online is a free online tool that works entirely in your browser — no signup, no data uploaded, no limits.

Add Watermark to PDF — Protect and Brand Your Documents

A watermark does more than just mark a document. It communicates context, asserts ownership, and deters unauthorized use all at once. When a client receives a PDF stamped CONFIDENTIAL, they understand immediately that the content is sensitive. When an investor sees DRAFT across every page, they know the numbers are preliminary. When your company name appears diagonally across a deliverable, it signals professionalism and ownership.

Tooliby's watermark pdf tool applies custom text watermarks to every page of your PDF simultaneously. You control the watermark text, position, color, font size, and opacity — everything needed to add watermark content that fits your specific document and purpose without obscuring the content beneath it.

Choosing the Right Opacity for Your Watermark

Opacity is the difference between a watermark that communicates and one that annoys. Too high and it obscures the content — readers struggle to focus on the actual text. Too low and it disappears, failing its purpose entirely. For most text watermarks on document pages, 20 to 35 percent opacity hits the sweet spot — clearly visible when you are looking for it, but not dominating the page.

For confidential business documents, higher opacity (40-50%) reinforces the sensitivity of the content. For subtle branding watermarks on client deliverables, lower opacity (15-20%) marks ownership without making the document feel restricted. Draft watermarks are typically set at 25-30% — noticeable but not obstructive.

Common Watermark Text to Use

CONFIDENTIAL is the most common business watermark, used on contracts, financial projections, and internal reports before they are finalized. DRAFT signals that content is not yet approved or final. SAMPLE marks demonstration documents sent before payment. COPY identifies duplicate documents in legal proceedings. Your company name or website as a watermark on published reports creates brand attribution that survives when someone saves or shares the document without proper credit.