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Flatten PDF

A filled form that cannot be changed and looks the same in every reader.

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

How to flatten PDF

  1. Drop the PDF.
  2. Nothing to choose.
  3. Press Flatten and download.

What happens to your file

Every form field and annotation — typed answers, ticked boxes, signatures placed as stamps, highlights, sticky-note markers — gets its appearance drawn into the page content and the interactive layer is removed. The page looks exactly as it did, in every reader, and nothing on it can be altered.

Text elsewhere on the page stays selectable; only the fields and marks become ordinary page content.

Questions

When should I flatten?

Before sending a filled form somewhere that must not change it, or when a form looks empty in another reader — the answers were there but only as fields that reader could not draw.

Is this the same as protecting the PDF?

No. Flattening removes the fields; Protect PDF adds a password and permissions. Both together is the belt and braces.

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.flatten",
    "options": {}
  }'

The same operation, pdf.flatten — Form fields and annotations drawn into the pages — no longer editable, everywhere the same. Upload first with the quickstart; every option is on the operations page. 500 free credits a month, then $5 per thousand.