Flatten PDF

1. Choose your PDF, or drop it onto the box. It opens in your browser, so the file never leaves your device. The tool tells you how many form fields and comments it found.
2. Pick how to flatten. Keep text selectable locks the form fields and comments into the page; Turn pages into images turns every page into a picture.
3. Click Flatten and download. You get a copy named yourfile-flattened.pdf; the original stays as it is.

Fill in the form and add any signature first: once a PDF is flattened, its boxes can no longer be typed into.

Form fields, comments and stamps normally float on top of a PDF page as separate, editable objects. Flattening draws them into the page itself, the way they look now, and removes the editable versions.

Keep text selectable is right for most forms and reviewed documents. The answers and comments are locked in, the file stays sharp at any zoom, and people can still search it, copy from it and use a screen reader with it. Choose Form fields or Comments and stamps on their own if you only want to lock one of them.

Turn pages into images is for when nothing should be editable or copyable at all, the way a printed-and-scanned copy behaves. It also helps when a reader shows a form oddly, because every page becomes a plain picture. The file is usually larger and text looks softer when you zoom in. Choose Print (300 dpi) if it will be printed, or Standard (150 dpi) for email and screens.

• Answers can’t be changed. A filled-in form stays fillable, so anyone who opens it can edit your answers. Flattening fixes them in place.
• Forms look the same everywhere. Some phone apps, email previews and printers show form fields empty or in the wrong font. Once flattened, the answers are part of the page, so every reader shows them.
• Comments and stamps stay put. Review marks, “Approved” stamps and signatures added as images can’t be moved, hidden or deleted by the next person.
• Printing and uploading work. Print shops and upload portals sometimes ignore form fields and comments, leaving gaps where your answers were.

• Keep the original. Flattening can’t be undone, so save the unflattened file in case you need to change something.
• Digital signatures stop being valid. A certificate-based signature only covers the file as it was signed. Flatten first, then sign, if the signature must stay valid.
• Flattening isn’t redaction. A black box drawn over text with a comment tool still has the text underneath it, and with Keep text selectable that text can still be copied. Remove sensitive text with a proper redaction tool.
• Flattening isn’t a password. It stops form fields and comments being edited, but someone with a PDF editor can still change the page itself. A password controls who can open or edit the file.

To remove comments instead of locking them in, use Remove PDF annotations.