Add an Image Watermark to a PDF

Overlay an image watermark (logo, stamp or signature) on every PDF page online: adjustable opacity and size, centered. Runs in your browser — nothing uploaded.

Files stay local .pdf、.png、.jpg、.jpeg Max 100MB
Drop files here, or click to choose
Supports .pdf · Max file size: 100MB
Watermark image (PNG / JPG):

Options

What this tool does

Add an image watermark to a PDF: overlay a logo, official stamp, signature or "CONFIDENTIAL" badge on every page. Compared with text watermarks, image watermarks keep brand colors and shape details — the mainstream choice for marking outward-facing documents.

Opacity (default 30% — subtle enough to keep body text readable) and width share are adjustable, with center or bottom-right positioning; the image keeps its aspect ratio, never stretched. Everything runs in your browser; files are never uploaded.

How to use

  1. Pick the PDF, then the image Once both files are in place, hit "Add watermark". Transparent-background PNG works best — a white-background JPG leaves a visible white rectangle on the page.
  2. Tune opacity and size Stamps look right at 60–80% opacity (must be readable); logos at 20–40% (never intrusive). Width is a percentage of the page's short side, so portrait and landscape pages both work.
  3. Download and check each page The watermark lands on every page (covers and blank pages included). To mark only some pages, extract those pages first with the page-extraction tool.

FAQ

Can the watermark be removed?

Technically, professional tools can strip drawing operators — an image watermark is not strong protection. It marks ownership and reminds readers; real leakage prevention needs encryption and permissions.

Why is transparent PNG recommended?

PNG supports alpha: pixels outside the logo can be fully transparent. JPG has no transparency, so a white box covers the page (low opacity softens it but PNG still wins).

Can I watermark only the first page?

All pages by default. To mark a subset: extract the target pages, watermark them, then merge back with the original.

Text or image watermark?

Quick text notices ("INTERNAL") suit the text watermark; brand assets like logos and stamps suit the image one. They stack.

Will the watermark print?

Yes. The watermark is part of page content and prints exactly as displayed; lower opacity prints lighter.

Are my files uploaded?

No. The PDF and watermark image are processed in a browser Worker; nothing leaves your device.

Limits

Watermark image must be PNG / JPG; no SVG or animated images.

All pages overlaid (page selection not offered — extract pages first); one watermark image per run.

Encrypted PDFs are rejected; up to 100MB per file.

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