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Watermark PDF

Your words, diagonally, at the opacity you choose.

More free conversions, where you upload. The Fylane extension does the same work inside any upload form, on its own free share every day.Add to Chrome

How to watermark PDF

  1. Drop the PDF.
  2. Type the watermark text and pick an opacity.
  3. Press Watermark and download.

What happens to your file

The text is drawn diagonally across each page in grey at the opacity you chose, over the existing content. Text underneath stays selectable.

A watermark is a mark, not a lock: it discourages reuse and identifies copies, but a determined editor can remove it. Use Protect PDF for access control.

Questions

Can I use an image as the watermark?

Not on this page — text only. The API supports both.

Does it cover the text underneath?

At the recommended opacity the page stays fully readable; at 50% it is deliberately intrusive.

Do it once, not on every form

Fixing a file here means downloading it and going back to the form. The Fylane extension does this work inside the form instead, on the file you already have.

And it keeps the result. The next application that asks for a résumé, a cover letter and a photo fills all three from one tap, each one refitted to what that site accepts.

Your files stay in the browser, encrypted, on your machine. Nothing is uploaded to keep them and nothing is sent anywhere to fill a form.

Filmed from the extension: three upload fields on a job application, filled from one tap.

Add to Chrome — freeWhat it does

Do this in code

curl -X POST https://api.fylane.dev/v1/jobs \
  -H "Authorization: Bearer $FYLANE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "file_id": "<file id>",
    "operation": "pdf.watermark",
    "options": {
      "text": "CONFIDENTIAL",
      "opacity": 0.3,
      "position": "diagonal",
      "size": "medium",
      "color": "grey"
    }
  }'

The same operation, pdf.watermark — Grey diagonal text across every page, opacity yours. Upload first with the quickstart; every option is on the operations page. 500 free credits a month, then $5 per thousand.