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How to Patch a Pokemon ROM in Under Ten Minutes

Patching sounds scarier than it is. A patch file is a small set of instructions that turns a clean ROM into the hacked game. You bring the ROM, the patch brings the changes, the patcher glues them together. None of the steps need an account, and nothing here installs anything secretly.

The two patchers, side by side

Pick one. The browser patcher is easiest; xDelta is the one that handles the biggest, newest hacks.

ROM Patcher JSBestxDelta cross
Installs anythingNoNo
Runs in browserYesNo, an app
Handles xdelta patchesYes, smallYes, all sizes
Best forMost hacksBig recent hacks

Patching, step by step

  1. Get a clean ROM from a cartridge you own

    Dump it with a cart reader or a homebrew console. A downloaded ROM is the part that is illegal, so do not start there.

  2. Download the patch file

    Grab the .xdelta or .ips file from the hack's release page. The patch is usually a few megabytes.

  3. Open the patcher and drop both files in

    The patcher asks for the patch and the clean ROM. Match the base the hack expects, almost always FireRed for GBA hacks.

  4. Apply and save the patched ROM

    Save it with a new name so you keep the clean ROM. The output is what your emulator opens.

  5. Open it in your emulator and test the title screen

    If the custom title screen shows, the patch applied. If the game is a black screen, the base ROM did not match, recheck step three.

Ninety percent of the bug reports I get are people who patched onto the wrong base, or onto a ROM they already patched. Start clean, every time.

A longtime ROM hack maintainer, release notes

When it goes wrong

Frequently asked questions
The patched ROM is a black screen

The base ROM did not match the patch. Recheck which base the hack expects, redump a clean copy, and patch onto that. Do not patch onto an already-patched ROM.

The patcher says the file is too big

Use xDelta instead of the browser patcher. The browser tool struggles with the largest modern hacks; xDelta handles any size.

My emulator says unsupported file type

Name the output file ending in .gba, .nds, or .gb matching the base. Some patchers let the extension default oddly; just rename it.

Do I need to do this every time I play

No. You patch once and keep the output file forever. After that, just open it in your emulator.

Patched and ready?

Pick a hack that earned its slot and start playing.