Pokémon ROM Patcher
Apply an IPS, UPS, BPS or xdelta patch to your Pokémon ROM without installing anything. Drop in your clean base ROM and the hack's patch file, press apply, and the patched game downloads straight back to you. Your files never leave your device.
Powered by RomPatcher.js (MIT). Runs locally in your browser. Pokepatched never sees your files.
How to patch a Pokémon ROM hack
- Find the hack and its base game. Every hack targets one exact ROM — usually the US 1.0 release of FireRed, Emerald or Crystal. The hack's page tells you which.
- Download the patch. It will be a small file ending in .ips, .ups, .bps or .xdelta, often inside a zip. Extract it first.
- Load both files above. Base ROM in slot 1, patch in slot 2. The patcher recognises the format automatically.
- Apply and play. Open the downloaded file in any GBA, NDS or GBC emulator. Start a new save — old saves won't carry over.
Want the longer version with screenshots of each step? Read how to patch a GBA ROM hack without bricking it.
IPS, UPS, BPS: what's the difference?
IPS is the oldest format. It has no checksum, so it will happily patch the wrong ROM and give you a game that crashes later. Double-check your base version with IPS hacks.
UPS and BPS both check the input file, so a wrong base ROM fails immediately instead of silently. BPS also handles large hacks efficiently, which is why most modern projects ship it.
xdelta is common for NDS hacks, where ROMs are far bigger. It works the same way here.
Common questions
Is this patcher safe? Does my ROM get uploaded?
Nothing is uploaded. The patch is applied by JavaScript running on your own device, and the finished file downloads straight back to you. Pokepatched never receives either file.
Which patch formats does it support?
IPS, UPS, BPS, APS, PPF, RUP, BDF, PMSR and xdelta/VCDIFF. Those cover practically every Pokémon ROM hack on GBA, NDS and GBC.
Why does the patched game crash or show a checksum error?
Almost always the wrong base ROM. Most GBA hacks expect the US version 1.0 of FireRed or Emerald; a European release or a 1.1 revision patches incorrectly. Each hack page on Pokepatched names the exact base it needs.
Does it work on my phone?
Yes, on any modern mobile browser. Pick the ROM and patch from your files, apply, and load the downloaded file in an emulator such as Delta on iPhone or a GBA emulator on Android.
Can I patch a ROM that already has a hack applied?
Only if the second patch was built for that. Patches are made against one specific file, so stacking hacks usually breaks both. Start from a clean ROM for each hack and keep the outputs separate.