Flatten a PDF — free, in your browser
Filled in a PDF form and want to stop anyone else from editing the fields? Flatten it here — the fields lock into the page. No upload, no account.
What we found testing it
We filled a job-application PDF (name, address, checkbox) and flattened it. After flattening, opening the file in a reader showed the values but the fields were no longer clickable or editable — exactly what you want before emailing a completed form. A form we hadn't filled flattened cleanly too (empty fields stayed empty and locked).
How to use it
- Open the Flatten PDF tool above and choose your PDF (ideally one with filled-in form fields).
- Click Flatten PDF. The engine processes it in your browser.
- A flattened.pdf downloads. Open it and check that the fields are no longer editable.
What flatten does
Flattening bakes interactive form fields (text boxes, checkboxes, dropdowns) into the page so their values can't be changed. It does not flatten separately-added annotations like highlights or comment notes — those stay editable. If you only need to lock form data before sharing, this is the right, lightweight step.
FAQ
Is flattening free and private?
Yes. Everything runs in your browser; the file is never uploaded.
Why flatten a PDF?
To lock a filled-in form so the recipient can read it but not change the answers — useful before emailing applications, contracts or intakes.
Does it lock highlights and comments too?
No. This tool flattens form fields only. Standalone highlights/comments remain editable.
Can I still read the text after flattening?
Yes — the values are visible on the page; they're just no longer in editable fields.
Will flattening reduce the file size?
Not significantly. It changes how fields are stored, not the page content.