Canonical: https://rom-weaver.com/ppf-undo

# Undo PPF patches online | rom-weaver

Undo a PPF3 patch using its stored original bytes and download a restored ROM locally in your browser. Requires the exact patch with undo data. No uploads.

[Open in browser](https://rom-weaver.com/ppf-undo)

[Documentation](https://rom-weaver.com/docs.md)

[Full guide](https://rom-weaver.com/docs/undo-ppf-browser.md)

## Restore the saved bytes

1. Open [PPF Undo](<https://rom-weaver.com/ppf-undo>).
2. Add the patched ROM and the original `.ppf` patch. You can add archives containing either or both.
3. If an archive contains several candidates, choose the ROM and PPF patch to use. Check the **Patched ROM** and **PPF patch** cards and any warnings about ignored inputs.
4. Enter a separate output filename. Choose its format in **Restore**; open **Options** to adjust compression.
5. Select **Restore original ROM**.

![PPF Undo with a restored 16-byte ROM ready to download](<https://raw.githubusercontent.com/rom-weaver/rom-weaver/main/docs/screenshots/ppf-undo-restored.webp>)

If an input is invalid, replace it before restoring. If the patch lacks undo data, use your clean backup. The tool cannot recover changes from other patches applied afterward.

## Check the restored copy

Compare the restored file's checksum with the known original using [Identify](<https://rom-weaver.com/docs/identify-roms-browser.md#compare-a-checksum>). Test the copy before replacing any file.

For the terminal command, see [CLI tools](<https://rom-weaver.com/docs/cli.md#tools>). [PPF background](<https://rom-weaver.com/docs/patch-formats.md#ppf>) explains the format.