Trim a ROM in the browser

Use Trim to remove padding from a supported ROM and download a smaller copy. Keep the original for future patches.

Open Trim

1. Enable Beta tools in Settings.
2. Open Trim.
3. Add the ROM or its archive.
4. Select the required member if an archive contains several candidates.
5. Wait for reading, checksumming, and identification to finish.

The trim support reference lists supported formats and restoration limits.

Save a trimmed copy

1. Check the selected file in the ROM card. Open Checks to record its original checksums.
2. Choose an output name and format.
3. Select TRIM & DOWNLOAD.
4. Read the warning, then select Trim ROM to continue.
5. Save the result and test it in the emulator or hardware you use.

A file without removable padding may have no useful size reduction. A format that is not supported cannot be made trimmable by renaming it.

Restore padding

The browser does not expose the CLI's restore-padding or revert-marker options. Use Trim and restore from the CLI when you need them.

Restoring padding does not always reproduce the original bytes. XISO and RVZ scrub cannot be reverted. Compression and trimming explains the difference.