PDF Tools
Watermark PDF
Add text or logo watermarks to selected pages without uploading or rasterising your PDF.
A complete PDF watermark editor in your browser
Text versus logo watermarks: Use a text stamp for confidential, draft, sample, copy, or approval status. Use a transparent PNG or another supported logo when brand identity matters. Both modes share position, rotation, opacity, tiling, and page controls.
Selected pages: Apply a mark to every page, only the first or last page, odd or even pages, a range such as 1-5,7, or a manual selection. The selection is validated before export.
Diagonal and tiled marks: A large diagonal stamp is conspicuous, while repeating marks are harder to crop away. Tile spacing and alternate rows adapt independently to portrait, landscape, rotated, and mixed-size pages.
Opacity guidance: Around 20–35% often works for centred proof stamps; a small footer or logo may need 40–70%. Check the selected-page preview so important content remains readable.
Quality and privacy: Existing pages are not rasterised. Searchable text, vectors, page sizes, images, and annotations remain in the PDF where supported. All active processing stays in the browser.
Protected PDFs and limits: Unlock encrypted PDFs before using this tool. Browser safety limits are 100 MB, 500 pages, and 10 MB per logo. Complex or unusually large PDFs may still exceed device memory.
Frequently asked questions
How do I add a watermark to a PDF?
Upload a PDF, choose Text Watermark or Logo Watermark, select pages, adjust the live preview, and download the locally generated PDF.
Can I add text to every page?
Yes. All pages is the default, and text may contain multiple lines.
Can I add a logo?
Yes. Use PNG, JPG, WebP, or SVG. PNG transparency is preserved; WebP and securely checked SVG files are rasterised locally before embedding.
Can I watermark selected pages only?
Yes. Choose first, last, odd, even, a custom range, or pages manually. Duplicate range entries are normalised.
Can I use a diagonal watermark?
Yes. Enter any rotation from -180 to 180 degrees or use a diagonal quick preset.
Can I tile a watermark?
Yes. Tiled mode adapts to each page size and provides horizontal spacing, vertical spacing, and alternate-row offset controls.
Does watermarking reduce quality?
The PDF pages are not converted to images. Watermark objects are drawn onto the existing pages, preserving original text, vectors, images, dimensions, and quality where pdf-lib supports the source PDF.
Can I watermark a password-protected PDF?
Not directly. The browser-local PDF engine cannot decrypt protected PDFs, so use Unlock PDF first and then watermark the unlocked copy.
Can I change opacity?
Yes. Watermark opacity ranges from 5% to 100%. Text backgrounds have a separate opacity control.
Are my PDFs uploaded?
No. PDF loading, logo preparation, watermark drawing, saving, and download preparation all happen in your browser.
Does it preserve searchable text?
Yes for supported PDFs. Existing pages are not rasterised, so searchable text remains text.
Does it preserve links?
Existing PDF page annotations, including links, are retained where the PDF library supports the document structure.
Does it work on mobile?
Yes. The editor stacks vertically, the page selector scrolls horizontally, and numeric X/Y controls avoid requiring drag gestures.
Is the watermark permanent?
The downloaded PDF contains the watermark as page content, but it is not a security control and a skilled PDF editor may be able to remove it.
Is there a file-size or page limit?
Yes. PDFs are limited to 100 MB and 500 pages, and logos to 10 MB, to reduce browser memory failures.