Glarso

Watermark PDF

Stamp a text watermark across every page of a PDF, right in your browser.

Drag & drop files here, or click to browse

One PDF — watermark is stamped on every page

Files never leave your device

Mark up a document before sharing it

Sending a draft, a sample, or a confidential file? Drop your PDF above, type the watermark text, adjust its opacity and size, and download a copy with the watermark stamped diagonally across every page.

Need page numbers instead? Try Add Page Numbers to PDF.

Frequently asked questions

Is my PDF uploaded to add the watermark?

No. The watermark is drawn onto the PDF entirely in your browser using an open-source PDF library — the file never leaves your device.

Can I control how visible the watermark is?

Yes — the opacity slider goes from a faint 5% to a bold 80%, and the size slider controls how large the text is.

Can I remove a watermark added by this tool?

Not with this tool — it only adds watermarks. Keep your original, un-watermarked file if you'll need it later.

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