The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Infinite Dreams (Publisher) (1 member)
- Infinite Interactive (Developer) (3 members)
- Infinite Stratos (Series) (2 members)
- Infinity Ward (Developer) (5 members)
- Initial release year (13 members)
- Insomniac Games (Developer) (11 members)
- Interactive art (Genre) (7 members)
- Interactive drama (Genre) (2 members)
- Intergrow (Publisher) (1 member)
- Internal resolution (207 members)
- International Games System (Developer) (0 members)
- International Games System Co (Developer) (1 member)
- Inti Creates (Developer) (3 members)
- Irem Corp. (Developer) (6 members)
- Irem Corp. (Publisher) (4 members)
- Iron Galaxy (Publisher) (1 member)
- Iron Galaxy Studios (Developer) (3 members)
- Iron Man (Series) (2 members)
- Irrational Games (Developer) (2 members)
- Isopod Labs (Developer) (1 member)
- Ivent Games (Developer) (1 member)
- Ivent Games (Publisher) (1 member)
- JV Games (Developer) (1 member)
- JV Games (Publisher) (1 member)
- Jackbox Games (Developer) (2 members)
- Jackbox Games (Publisher) (2 members)
- James Bond (Series) (4 members)
- Japan (Release region) (778 members)
- Japan Studio (Developer) (17 members)
- Jellyvision Games (Developer) (1 member)
- Jikkyou Powerful Pro Yakyuu (Series) (7 members)
- JoJo's Bizarre Adventure (Series) (3 members)
- Joe Danger (Series) (2 members)
- Johnson-Voorsanger Productions (Developer) (2 members)
- JoyBits (Developer) (3 members)
- Joysound (Series) (1 member)
- Juice Games (Developer) (1 member)
- Just Add Water (Developer) (4 members)
- Just Dance (Series) (8 members)
- KMM Interactive Entertainment (Developer) (1 member)
- Kadokawa Games (Developer) (1 member)
- Kadokawa Games (Publisher) (3 members)
- Kaga Create (Developer) (1 member)
- Kaga Create (Publisher) (1 member)
- Kaiko (Developer) (1 member)
- Kalypso Media (Publisher) (5 members)
- Kamen Rider (Series) (5 members)
- Kane & Lynch (Series) (2 members)
- Kaos Studios (Developer) (1 member)
- Karaoke Revolution (Series) (3 members)
- Kart racing (Genre) (9 members)
- KatGames (Developer) (1 member)
- Keen Games (Developer) (1 member)
- Kemco (Publisher) (2 members)
- Kero Makura (Developer) (1 member)
- Kero Makura (Publisher) (1 member)
- Key (Developer) (3 members)
- Keystone Game Studio (Developer) (1 member)
- Killzone (Series) (3 members)
- King Art Games (Developer) (2 members)
- Kingdom Hearts (Series) (2 members)
- Klei Entertainment (Developer) (3 members)
- Klei Entertainment (Publisher) (1 member)
- Koch Media (Publisher) (4 members)
- Koei Canada (Developer) (1 member)
- Koei Tecmo (Developer) (28 members)
- Koei Tecmo (Publisher) (70 members)
- Koihime†Musou (Series) (2 members)
- Kojima Productions (Developer) (7 members)
- Konami (Developer) (21 members)
- Konami (Publisher) (78 members)
- Krome Studios (Developer) (4 members)
- Kuju Entertainment (Developer) (1 member)
- Kuju Entertainment (Publisher) (1 member)
- Kung Fu Factory (Developer) (4 members)
- Kung Fu Panda (Series) (3 members)
- Kuno Interactive (Developer) (1 member)
- Kush Games (Developer) (4 members)
- Kylotonn (Developer) (11 members)
- Kyouraku Sangyou Holdings (Developer) (2 members)
- Kyouraku Sangyou Holdings (Publisher) (2 members)
- LEGO (Series) (3 members)
- LOOT Entertainment (Publisher) (2 members)
- La Voz (Series) (2 members)
- Lancarse (Developer) (1 member)
- Land Ho! (Developer) (1 member)
- Laughing Jackal (Developer) (1 member)
- Laughing Jackal (Publisher) (1 member)
- Le Cortex (Developer) (1 member)
- Le Tour de France (Series) (5 members)
- Leader (Publisher) (1 member)
- Learning With the PooYoos (Series) (2 members)
- Left Field Productions (Developer) (3 members)
- Legacy parameters used (Config) (0 members)
- Lesta Studio (Developer) (1 member)
- Lesta Studio (Publisher) (1 member)
- Level-5 (Developer) (3 members)
- Level-5 (Publisher) (1 member)
- Lexis Numérique (Developer) (4 members)
- Lexis Numérique (Publisher) (5 members)