Flatten PDF
Filled in a PDF form? Flatten it so your answers become a permanent part of the page — nobody can change or wipe them, and it looks the same in every app.
Drop your file hereTap to add your file
or click to choose · nothing leaves your device
Private by design. This tool runs entirely in your browser — your file is processed on your device and is never uploaded to us. How this works
Ever filled in a PDF form on your computer — a job application, a tax form, a school permission slip — and worried the boxes could still be edited or accidentally emptied after you send it? Flattening is the fix. It takes the parts of a PDF that are still “live” and editable — the boxes you typed into, checkmarks, comments, highlights — and merges them permanently into the page. What you see becomes what everyone gets: fixed, final, and identical in every PDF reader.
It’s like printing the document and scanning it back in so the content is “set” — except Ream does it digitally, in a second, and (in the default mode) keeps your text crisp and selectable. Two modes cover every case, and it all runs in your browser: nothing is uploaded, no account, no watermark.
Flattening doesn’t change how your document looks, and it won’t noticeably change the file size — it only changes what can still be edited. Your original is never touched: you always get a new, finalized copy to download, so you can keep the editable version safely alongside it.
How it works
In form-fields mode, Ream merges the interactive AcroForm fields into the page content and drops the form, so the values stay visible but become permanent. In rasterize mode, each page is rendered to an image and rebuilt as a picture — which flattens annotations, stamps and layers too, at the cost of selectable text. Choose fields mode to keep text sharp; choose rasterize when you need to flatten everything, including comments and markup.
How to Flatten PDF
Add your PDF
Drop the file onto the box above or click to browse. It stays on your device.
Pick a flatten mode
Form fields keeps text sharp and selectable. Everything rasterizes each page to flatten annotations and layers as well.
Flatten & download
Ream flattens the file in your browser and hands you a finalized PDF. Keep your original if you might need to edit it again later.
What “flattening” actually does
A normal PDF form keeps your answers in a separate interactive layer that floats on top of the page. That’s why a reader can click a field and retype it, why a stray key-press can empty it, and why the same form can look slightly different from one app to the next.
Flattening removes that layer and stamps the values straight onto the page — so a filled field stops being a “field” and simply becomes part of the document, like ink on paper. The result: it can’t be re-edited or cleared, it displays identically everywhere, and no hidden field values are left inside the file.
Which mode should you use?
| Mode | Best for | Text stays selectable? |
|---|---|---|
| Form fields | A completed form you want to lock | Yes |
| Everything (rasterize) | Removing annotations, stamps, comments and layers | No — pages become images |
Start with form fields — it’s lossless and keeps your document sharp. Only reach for rasterize when you specifically need to flatten markup or interactive content that isn’t a form field.
Why flatten a PDF?
Flattening is about finality and consistency. A flattened form can’t be re-edited or accidentally cleared, and it displays identically in every reader — some viewers render interactive fields differently, which flattening removes as a variable. It’s the right last step before you send a filled application, a signed form or a marked-up proof.
Flatten, redact or protect?
These solve different problems. Flatten locks the appearance so it can’t change. To truly remove hidden or sensitive content, use Redact PDF (which rasterizes redacted pages so nothing is recoverable). To stop people opening the file at all, add a password with Protect PDF.
Why choose Ream
Locks in filled forms
Baked-in field values can’t be changed, cleared or re-edited.
Two modes
Keep text sharp with form-field flattening, or rasterize to flatten everything.
Runs in your browser
Nothing is uploaded — the file never leaves your device.
Free, no watermark
No account, no watermark, no limits.
Frequently asked questions
What does flattening a PDF do?
It bakes interactive elements — filled form fields, annotations — into the page so they become a permanent, non-editable part of the document.
When should I flatten a PDF?
Right before you send, print or archive a filled form or a marked-up document — so the answers and notes can’t be changed or accidentally cleared, and it looks the same in every reader.
Can I un-flatten a PDF later?
No — flattening is permanent by design; the fields become part of the page. Keep a copy of the original if you might need to edit it again.
Will my text stay selectable?
In form-fields mode, yes. In rasterize mode the pages become images, so text is no longer selectable.
Does it flatten annotations and comments?
Use the rasterize mode for that — it flattens every layer, including annotations and stamps. Form-fields mode only flattens form fields.
Is my file uploaded?
No. Flattening runs entirely in your browser, so the PDF stays on your device.
Is this the same as redacting?
No. Flattening locks the appearance; Redact PDF removes underlying content so it cannot be recovered.
Is it free?
Yes — free, no sign-up, and no watermark.