BPS Patcher
BPS patches carry their own checksum, so a bad match gets caught before it corrupts anything. Drop your ROM and .bps file in below — it applies entirely on your device.
Modern, Pokemon-hack favorite
Why Hack Creators Reach for BPS
IPS never checked whether it was touching the right file. BPS was built specifically to fix that — it records a checksum for the source ROM and the finished result, so the patch itself can tell you when something doesn't line up. That's why it's become the go-to format for actively maintained ROM hacks that get updated often: creators would rather their patch fail loudly than silently hand someone a broken game.
Step-by-Step
Line up your base ROM
Check the hack's page for the exact game and revision it's built against. BPS will reject a mismatch rather than risk a broken patch.
Grab the .bps file
It's usually distributed as a single file next to the ROM hack's release notes.
Select both in the patcher
The format is read from the file header automatically — you don't need to tell it what it's looking at.
Apply and download
BPS verifies the output against its own recorded checksum before handing you the file, so a successful download means it's correct.
Mistakes That Trip Up BPS Patching
Ignoring the checksum-mismatch error
BPS rejects the wrong ROM on purpose — it's not a bug in the patcher. Track down the exact base ROM version the hack lists, not just "the same game."
Mixing up which file is the ROM and which is the patch
The dropzones don't care about labels the way a human would — check that your original game file went into the ROM slot before applying.
Expecting a BPS patch to work on a related but different game
BPS patches are built byte-for-byte against one source file. A patch made for one revision of a game won't apply to a different regional release.
Troubleshooting
"Invalid input ROM checksum" error
This is BPS doing its job — the ROM you selected doesn't match what the patch was built against. Re-check the region, revision, and that the file isn't already modified.
Learn morePatch applies but the game won't boot
Rare with BPS since it checks both ends, but worth confirming the output extension matches what your emulator expects for that platform.
Learn morePatch file itself won't load
Confirm the .bps file downloaded completely — a truncated download is the most common reason a patch file fails to parse at all.
Learn moreFAQ
Related Guides
BPS checks its own work, but the patcher still runs entirely in your browser — nothing is uploaded either way.
Open the ROM PatcherNot sure BPS is what you need? Compare it against IPS, UPS, and xdelta.