When should I flatten?

Before sharing a completed form, so the recipient sees your answers exactly as filled and can't accidentally (or deliberately) edit them.

Can I undo it afterward?

No, once a field is baked into static content there's no interactive layer left to restore. Keep the original file if you might need to edit the answers again.

Is the document uploaded to flatten it?

No. pdf-lib rewrites the form in this tab, and the flattened file downloads directly from your device.

Flatten PDF

No upload · runs in your browser

Drop a PDF to flattenProcessed in your browser. No uploadSelect files No upload · processed locally · auto-deleted

How it works

How to flatten a PDF form for free

Drop a filled PDF form and FernPDF flattens its fields into permanent page content, then downloads the locked copy. The values become part of the page and can no longer be edited.

Flattening runs entirely in your browser, so completed forms with personal details are never uploaded to a server.

FAQ

It bakes interactive form fields into the page as static content. The filled-in values stay visible but can no longer be changed or cleared.

Keep going