The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Hydravision Entertainment (Developer) (4 members)
- Hydravision Entertainment (Publisher) (1 member)
- Hyperdimension Neptunia (Series) (3 members)
- I-Friqiya (Developer) (1 member)
- I-Friqiya (Publisher) (1 member)
- IO Interactive (Developer) (5 members)
- ISquared Games (Developer) (1 member)
- ISquared Games (Publisher) (1 member)
- Id Software (Developer) (3 members)
- Idea Factory (Developer) (11 members)
- Idea Factory (Publisher) (5 members)
- Idol Minds (Developer) (3 members)
- Ignition Entertainment (Publisher) (7 members)
- Ignition Tokyo (Developer) (1 member)
- Ilusis Interactive Graphics (Developer) (1 member)
- Ilusis Interactive Graphics (Publisher) (1 member)
- Imageepoch (Developer) (1 member)
- Images (1 member)
- ImaginEngine (Developer) (1 member)
- Immersion Games (Developer) (2 members)
- InFamous (Series) (3 members)
- InFramez Technology (Developer) (1 member)
- InFramez Technology (Publisher) (1 member)
- InXile Entertainment (Developer) (2 members)
- InXile Entertainment (Publisher) (2 members)
- Incinerator Studios (Developer) (3 members)
- Incognito Entertainment (Developer) (2 members)
- Incorrect IRD parameter (GameID) (44 members)
- Incorrect configurations (Config) (1 member)
- Incorrect game mode parameter (Infobox) (0 members)
- Incorrect release type parameter (Infobox) (0 members)
- IndiePub (Publisher) (1 member)
- IndiePub Entertainment (Publisher) (1 member)
- IndiePub Games (Publisher) (1 member)
- Infinite Dreams (Developer) (1 member)
- Infinite Dreams (Publisher) (1 member)
- Infinite Interactive (Developer) (3 members)
- Infinite Stratos (Series) (2 members)
- Infinity Ward (Developer) (5 members)
- Initial release year (14 members)
- Insomniac Games (Developer) (11 members)
- Interactive art (Genre) (7 members)
- Interactive drama (Genre) (2 members)
- Intergrow (Publisher) (1 member)
- Internal resolution (215 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)