Add Watermark to PDF
Processing entirely on your device — large files may take a moment.
Type your text once and every page gets the same stamp — centered, translucent (18% opacity) and sized relative to the page width, so A4 and slide-format pages both read naturally.
The watermark is real PDF text drawn with a standard font — it survives printing and copy-paste checks, and the rest of the document (text, links, forms) is untouched.
How to watermark PDF
- 1
Select your files
Drag & drop your PDF files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Set the options above and click the button. Processing runs entirely inside your browser using WebAssembly.
- 3
Download results
Download each converted PDF file individually, or grab everything at once as a ZIP archive.
About the PDF format
PDF (Adobe, 1993; ISO 32000 since 2008) exists for one promise: the document looks identical everywhere, forever. Fonts get embedded, layout is fixed to the point, and a contract printed from a 2003 file renders the same as one created this morning. That fixed-layout guarantee made it the standard for invoices, manuals, forms, e-books and anything with legal or financial weight.
The same design is what makes PDFs stubborn. They are meant to be presented, not edited — text lives in positioning operators rather than paragraphs, so extraction and re-flow are approximations. Scanned PDFs are worse: pure images with no text layer at all until OCR enters the picture. Still, no other format comes close for final-form document delivery.
+Strengths
- ✓Pixel-identical rendering on every device and printer
- ✓Fonts, images and color profiles travel inside the file
- ✓Mature ecosystem: forms, signatures, annotations, encryption
!Limitations
- −Hard to edit by design — even small changes need tooling
- −Text extraction is an approximation, not a conversion
- −Scanned PDFs are images without OCR
Frequently asked questions
Can I watermark only some pages?
This page stamps every page. Use the extract/delete-pages tools to build a subset first, then watermark it.
Can I use an image logo instead of text?
Text-only for now — image stamps with positioning controls are on the roadmap.
Is the watermark removable?
No tool can promise that. A translucent stamp deters casual reuse; for legal protection, registered DRM or digital signatures are the proper instruments.