When you fill in a PDF form, the answers live in interactive fields that anyone can still edit, and that some viewers display differently or not at all. Flattening takes the current values of those fields, along with comments, highlights and stamps, and draws them permanently onto the page. The result looks the same everywhere and can no longer be modified with a form filler.
It's a good last step before submitting an application, archiving a completed form, or sending a document whose annotations must not get lost when someone prints it. Your file is uploaded securely over HTTPS, processed on our servers and deleted automatically within an hour.
Keep an unflattened copy if you might need to change the answers later; flattening can't be reversed.
How to Flatten PDF
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1
Upload the PDF
Choose a filled form or annotated document.
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2
Flatten
Fields and annotations are merged into the page content.
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3
Check
Open the result to confirm everything appears as expected.
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4
Download
Save the flattened PDF.
Features
Form fields baked in
Text boxes, checkboxes and dropdown selections become regular page content.
Annotations preserved visually
Comments, highlights and stamps are drawn onto the page so they print reliably.
Consistent display
Flattened documents look the same in every viewer, including ones with poor form support.
Good to know
- Flattening is permanent; fields can't be edited afterwards.
- Flattening is not a security measure. Text drawn on the page can still be copied, and it doesn't hide anything. Use Redact PDF to remove information.
- Maximum 100 MB and 500 pages per file.
Frequently asked questions
Why would I flatten a PDF?
To make filled-in answers and annotations permanent, prevent accidental edits, and ensure the document looks the same in every viewer and when printed.
Can I unflatten a PDF later?
No. Once fields are converted to page content they can't be turned back into fillable fields. Keep the original if you may need to edit it.
Does flattening protect my PDF?
It stops casual editing of fields, but it is not encryption. To restrict access, use Protect PDF; to remove sensitive content, use Redact PDF.
Should I flatten after signing?
Often, yes. Flattening after Sign PDF makes the signature image part of the page, so it can't be easily moved or deleted as an object.
How long do you keep the file?
It is deleted automatically within an hour, and you can delete it yourself immediately after downloading.