What does flattening a PDF mean?
It merges the interactive parts of a PDF, like form fields and comments, into the page itself. They still look the same, but nobody can edit them anymore.
PDF Tools
Flatten PDF
Lock filled forms, comments and stamps into the page so they cannot be edited.
Stays in your browser: your files are never uploadedFree: 3 uses a day, 5 with a free account. Unlimited on Pro
Drop your PDF here
Lock in filled forms, comments and signatures so they cannot be changed.
Your file stays private. Flattening happens in your browser and nothing is uploaded.
How it works
1
Add your PDF
Drop a filled form or annotated PDF into the box. It is read in your browser and nothing is uploaded.
2
Choose what to flatten
Flatten forms and annotations together, or only the form fields and keep comments editable.
3
Download
Your flattened PDF downloads instantly. It looks the same, but the answers can no longer be changed.
Flatten PDF features
- Locks form answers, checkboxes and dropdown choices into the page.
- Flattens comments, highlights, stamps and drawn signatures too.
- Shows how many fields and annotations were found before you start.
- Fixes forms that look blank or different in some PDF readers.
- Runs in your browser, so the file is never uploaded.
- No watermarks and no signup needed.
Flatten PDF FAQ
Why should I flatten a filled form?
So the answers cannot be changed after you send it, and so it looks the same in every PDF reader and printer. Many offices ask for flattened forms.
Can I undo flattening?
Not in the new file. Keep your original PDF if you might need to change the answers later.
Will my signature stay visible?
Yes. Drawn or stamped signatures are kept exactly where they are. Digital certificate signatures are not kept, because flattening changes the file.
Do my files get uploaded?
No. Flattening runs entirely in your browser on your own device.
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