Flatten PDF

No. Flattening makes form fields and annotations appear fixed in most PDF viewers, but it does not encrypt the document, remove hidden metadata, or prevent a determined user from opening and modifying the file in advanced tools. For password protection, use Protect PDF. For tamper-evidence, use a digital signature tool.

No. Flattening does not remove document metadata such as author, creation date, or revision history. Use a dedicated sanitize tool (not included here) if metadata removal is required.

Placed signature images and text are flattened along with other form fields and annotations. Cryptographic digital signatures (signed with a certificate) should not be flattened because doing so invalidates the signature — keep those documents untouched or use dedicated signature-preserving tools.

Yes. The original file on your device is never modified. Flattening produces a new PDF that you download. Keep a copy of the original if you expect to edit the form fields again later.

No. Flattening runs in your browser using pdf-lib. The file never leaves your device.