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Flatten PDF
Merge layers and form fields. Free, no sign-up.
or drop it here
Flatten PDF runs inside your browser — your file never reaches our servers.
How to flatten PDF
Flattening turns interactive parts of a PDF into permanent page content — the usual last step before sending a filled form.
- Select your PDF. A filled form, or a document with annotations.
- Choose how flat. Fields only keeps text selectable; Everything rebuilds pages as images.
- Download. A document whose contents can no longer be edited as fields.
Two modes, two very different files
Form fields only takes the interactive form apart and puts it back as page content: each field's current appearance — the text typed into it, the tick in the box — is drawn into the page, and the field itself is removed. There is nothing left to edit or clear, but the values are still real text, so they select, copy and search; links and comments keep working; and the file stays about the size it was.
Everything takes a different route. Each page is re-rendered exactly as it appears and stored as a JPEG at 150 dpi — an A4 page becomes an image of about 1,240 × 1,754 pixels — and a fresh document is built from those images. Nothing survives as an object: no fields, no annotations, no links, no bookmarks and no text layer, so the result cannot be searched or copied from. A text document usually comes out several times larger; a scan often comes out smaller.
When flattening is the wrong tool
Flattening is not redaction. A flattened value can no longer be edited, but it is still there in full view — and even the rasterised mode simply photographs what was on the page. If something has to be gone rather than fixed, use Redact PDF, which removes the text and rebuilds the page around it.
It is not a comment remover either, in the mode most people choose. Form fields only touches the form and nothing else, so highlights, sticky notes and ink drawings pass through untouched and stay editable in any reader. If the comments are what you want gone, open the file in Comment & review, delete the threads and save. And if the real goal is a smaller file, Compress PDF makes that trade deliberately: it keeps its lossless result whenever rasterising would come out bigger.
Questions
Which mode should I use?
Form fields only, almost always — it locks the values while keeping text selectable and the file small. Choose Everything only when you truly need no annotations or layers to survive; it removes the text layer and makes the file larger.
Can flattening be undone?
No. Keep your original — the flattened copy is a one-way result.
Will a flattened form still be accepted as a filled-in form?
For a human recipient, yes — the values are ordinary page content, they print identically and nobody can alter them by accident. For a system that reads the form data out of the file, no: flattening removes precisely the fields it reads. Send the unflattened form to anything that processes submissions automatically.
Can I flatten only some pages?
Not in one pass — the setting applies to the whole document. Pull the pages out with Extract pages, flatten those, then put them back with Merge PDF or Insert pages.
What happens if my PDF has no form fields at all?
Form fields only has nothing to flatten, so you get the same pages back, re-saved. If the aim was to fix the appearance of a document with annotations or layers, Everything is the mode that changes something — at the cost of the text layer.
Are my files uploaded to a server?
No. Every tool on this site runs inside your browser, using the same engine as the Folia desktop app. Your file is read from your disk into your browser’s memory, processed there, and handed back as a download. It never crosses the internet, so there is nothing for us to store, leak or hand over.
Is there a file size limit?
We impose none. The only ceiling is your own device’s memory, which differs from one computer to another — so we read what your browser reports about this machine and show the resulting limit on the page. Light tools like merge and rotate handle far more than heavy ones like OCR, which must render every page. For anything larger, Folia for Desktop has no limit at all.
Is it really free? Do I need an account?
Yes, and no. Every tool is free and unlimited, with no watermark and no sign-up. Ads pay for the site, and your own computer does the work, which costs us nothing. Signing in with a paid Folia plan simply removes the ads.