Flatten a PDF
Lock form answers and comments into the page so they can’t be changed.
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How to use Flatten PDF
Add your PDFs
Drop one or more PDFs onto the page. For the first file you’ll see what was found, such as 12 form fields, 5 comments and 3 links.
Choose what to flatten
Leave Form fields and Comments and markup ticked, or untick one. Keep links is on by default, so links stay clickable.
Flatten and download
Click Flatten PDF and save your file. Several files come back together as a ZIP.
Why use Utils365
Answers that stay put
Typed answers, ticks and choices become part of the page, so nobody can change them by clicking into the form.
Looks the same everywhere
Highlights, notes, stamps and drawings are drawn exactly as they look now, so every reader and printer shows the same page.
Links still work
Web and page links stay clickable unless you choose to remove them.
Your file stays with you
Everything happens in your browser, so your PDFs are never uploaded to a server.
Frequently asked questions
What does flattening a PDF do?
It turns interactive layers, such as form fields and comments, into ordinary page content. The page looks the same, but the answers and markup can no longer be edited, moved or deleted in a PDF reader.
Why flatten a filled-in form?
So the answers can’t be changed after you send it, and so it shows the same in every app. Some readers and printers skip form fields or show them blank; a flattened form always shows your answers.
Will links still work?
Yes, as long as Keep links is ticked, which it is by default. Untick it to remove all links.
Can I undo flattening?
Not in the flattened file, so keep your original if you might need to edit the form again. Flattening makes a new copy and leaves your original as it was.
What happens to sticky notes?
The note icon is drawn onto the page where it was, and the pop-up text is removed. To keep the text readable, copy it out before flattening.
Does it work with forms in Chinese or other scripts?
Yes. Answers keep the look they already have in the file, so text in any language appears just as it did before.
Can I flatten a password-protected PDF?
Remove the password first with Unlock PDF, then flatten it. To stop others editing it afterward, use Protect PDF.