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HomePDFFlatten PDF

Flatten PDF

Flatten supported PDF form fields. Free, private, runs in your browser.

100% private — your files and text never leave your browser. All processing happens locally on your device.

Choose a file

or drop it here

PDF·Up to 200MB
Flattening can invalidate digital signatures. It removes interactive form fields but is not redaction — hidden data may remain.

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What Flattening Changes

Flatten PDF converts supported AcroForm field appearances into normal page content and removes the editable widgets from the saved copy. It is useful before sharing completed forms or archiving simple submissions.

What Flattening Does Not Guarantee

Flattening is not a security cleanup or redaction process. It does not guarantee removal of hidden layers, embedded files, comments, object history, or content outside the visible page.

Local PDF Rewriting

The PDF is loaded and rewritten in the browser with pdf-lib. Convertful does not upload your form, but rewriting can invalidate signatures or certification workflows, so keep the signed original.

FAQ

What does flattening a PDF do?

For supported AcroForm fields, flattening turns the field appearance into normal page content and removes the editable form widgets from the saved copy.

Is flattening the same as redaction?

No. Flattening does not guarantee removal of hidden content, layers, embedded files, comments, object history, or text outside the page view.

Does the PDF upload?

No. Convertful loads the PDF in your browser, uses pdf-lib to flatten supported fields, and creates the download locally.

Can flattening affect signatures?

Yes. Any rewrite can invalidate digital signatures or certified-document workflows. Keep the original signed PDF if signature status matters.

Why did my PDF not change much?

If the PDF has no supported AcroForm fields, it may already be flat or may use unsupported XFA/custom form structures.