| .ibch |
IncrediBots Challenge File |
| .icmod |
Inner Core Minecraft PE Mod File |
| .imga |
Aleph One Image File |
| .ibro |
IncrediBots Robot File |
| .i3pack |
Point Blank Game Data File |
| .itk |
ScummVM Game Data File |
| .ib2 |
IncrediBots 2 Saved Challenge File |
| .ib3 |
IncrediBots 3 Saved Challenge File |
| .j2l |
Jazz Jackrabbit 2 Level File |
| .j2i |
Jazz 2 Internet Link File |
| .jg4 |
BigJig Jigsaw Puzzle |
| .jam |
Line 6 Device Recording |
| .jap |
Nonogram Puzzle File |
| .jst |
Jnes Save State |
| .jmf |
Jackhammer Project |
| .ja |
Jet Archive |
| .jag |
Jagex Data File |
| .jkb |
Jedi Knight Bot File |
| .jcr |
Nonogram Puzzle File |
| .jbeam |
BeamNG Vehicle Definition Format |
| .jrz |
PSP Game Data File |
| .jigsaw |
Jigsaw Explorer Save File |
| .jrc |
PCjr Cartridge ROM File |
| .kar |
Karel Function Dictionary |