Flatten PDF

Lock in filled form values so they cannot change.

    Runs in your browser. Your files never leave your device.

    How to flatten a PDF

    1. Fill in the PDF's form fields in another app first, then save it.
    2. Drop the filled PDF here.
    3. Download the flattened copy.

    What flattening changes

    Before flatteningAfter flattening
    Text field valuesEditable, click to changePrinted as page content
    Checkboxes and radio buttonsCan be toggledFixed as they were left
    Dropdown selectionsCan be reopened and changedShown as plain text
    Comments and drawn markupPresent and editableUnchanged
    LinksClickableUnchanged

    Only the AcroForm fields, meaning text boxes, checkboxes, radio buttons and dropdowns, are affected. Everything else on the page stays exactly as it was.

    Why flatten a filled form

    • Stops a recipient from accidentally clearing a field or changing an answer after you send it.
    • Keeps the filled text looking identical in Adobe Acrobat, Preview, browsers and phone PDF apps, since each of those can otherwise render an unflattened field's font and alignment slightly differently.
    • Makes a signed release, application or intake form final before it goes into a shared folder or an archive.
    • Prepares a form for printing or scanning back in, since some print drivers ignore live form fields.

    Fill first, then flatten

    This tool only locks in values that are already in the fields. It has no form editor of its own, so fill out the PDF first in whatever app you normally use, save it, and then drop the filled copy in here.

    If a field is left blank, it stays blank after flattening, it just becomes permanent blank space instead of a fillable box.

    Flatten PDF FAQ

    What exactly does flattening change?

    The current value of every form field, such as text boxes and checkboxes, is drawn directly onto the page, and the fields stop being editable. Other annotations like comments or drawings are left as they are.

    Why would I want to flatten a PDF?

    It stops someone from accidentally or deliberately changing answers after you send the form, and it makes the filled-in text show consistently in every PDF viewer.

    What if my PDF has no form fields?

    The file downloads unchanged, since there is nothing to flatten.

    Can I flatten several filled PDFs at once?

    Yes. Drop them all in and download them individually or as a ZIP.

    Does flattening remove comments or highlights?

    No. Sticky notes, highlights and drawn markup are separate from form fields, so they stay exactly as they were. Only the interactive form fields are affected.

    Can I undo a flattened PDF?

    No. Once a field is flattened it cannot be turned back into an editable field. Keep the original filled PDF somewhere safe if you might need to change an answer later.

    Will flattening change my file size much?

    Usually only a little. It redraws the same field values as page content instead of adding anything new, so the size stays close to the original.

    Does flattening affect a signature I added elsewhere?

    A signature image placed with a tool like Sign PDF is already part of the page, not a form field, so flattening does not change it.

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