Flatten PDF — Lock Forms and Annotations
Turn filled-in form fields, comments, highlights and stamps into a permanent part of the page, so they look the same everywhere and can no longer be edited.
Drop a PDF here or
Your file never leaves your device. Everything happens in this browser tab: no upload, no server copy.
How to flatten a PDF
- Fill in your form or finish your comments in any PDF app, then save it.
- Drop the PDF onto the box, and choose whether to flatten form fields, annotations, or both.
- Click "Flatten PDF". The flattened copy downloads with everything locked into the page.
Why flatten a PDF?
Form fields and annotations sit on top of the page as separate, editable layers. That causes problems once a form is finished: anyone can change your answers, some apps and printers show the fields empty or in the wrong font, and online portals sometimes reject files with live fields. Flattening draws each field and comment into the page itself, exactly as it currently looks, and removes the editable layer.
Flatten a PDF before sending a completed application, tax form or contract summary, before printing through a service that drops form data, or before merging forms that share field names (which would otherwise overwrite each other).
What is kept
The page content, text and images are untouched, and the result looks the same as before. Links stay clickable. Each annotation is drawn using the appearance saved in the file; the rare annotation that has no saved appearance is left in place, and the result message tells you if that happened. Flattening cannot be undone, so keep your original if you may need to edit it again.
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Frequently asked questions
Are my files uploaded?
No. Your PDF is opened and processed by JavaScript in this browser tab. Nothing is sent to a server and no copy is kept.
Can a flattened PDF be edited again?
The form fields and comments become part of the page, so they can no longer be changed as fields. Keep your original file if you might need to edit it.
Will my filled-in answers be kept?
Yes. Fields are drawn exactly as they appear now, including text, checkmarks and selected options.
Is text still searchable after flattening?
Text that was already part of the page stays searchable. Form field values usually become searchable text too.
Does flattening reduce file size?
Usually a little, because the form definitions are removed. Use Compress PDF for bigger savings.