LHTSOFT PDFBETA
Fast. Powerful. Free. · PUBLIC BETA

Add a watermark to PDF

Stamp a visible diagonal watermark on chosen PDF pages. Adjust text, size, angle and transparency in your browser. This does not provide copy protection.

Open free PDF editor →

Browser-only file processing · No login · No watermark

How it works

  1. Open your PDF in the private workspace.
  2. Choose Watermark & Page Numbers, enter text and optional page range.
  3. Apply the watermark and download the updated PDF.

Beta release: features are introduced only after validation. General-purpose existing PDF text replacement, certified signatures, office document conversion and guaranteed irreversible redaction are not supported. The editor has narrowly limited experimental text replacement. Keep a backup of your originals.