The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Alpha Denshi (Developer) (2 members)
- Alvion (Developer) (1 member)
- Alvion (Publisher) (1 member)
- Amanita Design (Developer) (1 member)
- Amanita Design (Publisher) (1 member)
- American Laser Games (Developer) (3 members)
- American football (Genre) (27 members)
- Angry Birds (Series) (2 members)
- Anisotropic filter: 16x (Config) (3 members)
- Anisotropic filter: Auto (Config) (28 members)
- Anti-aliasing: Auto (Config) (2 members)
- Anti-aliasing: Disabled (Config) (12 members)
- ApolloSoft (Developer) (1 member)
- Aqua Plus (Publisher) (1 member)
- Aquaplus (Developer) (6 members)
- Aquaplus (Publisher) (7 members)
- Ar Tonecilo (Series) (1 member)
- Arc System Works (Developer) (16 members)
- Arc System Works (Publisher) (15 members)
- Arcade (Genre) (1 member)
- Arkane Studios (Developer) (1 member)
- Arkedo Studio (Developer) (2 members)
- Armature Studio (Developer) (1 member)
- Armored Core (Series) (4 members)
- Army of TWO (Series) (3 members)
- Arrowhead Game Studios (Developer) (1 member)
- Artdink (Developer) (6 members)
- Artech Studios (Developer) (1 member)
- Artificial Mind and Movement (Developer) (3 members)
- Artillery (Genre) (4 members)
- Artoon (Developer) (1 member)
- Ascaron (Developer) (1 member)
- Asobo Studio (Developer) (4 members)
- Aspect ratio: 16:9 (Config) (0 members)
- Aspyr Media (Publisher) (1 member)
- Assassin's Creed (Series) (9 members)
- Asynchronous texture streaming: Off (Config) (5 members)
- Asynchronous texture streaming: On (Config) (22 members)
- Atari (Developer) (2 members)
- Atari (Publisher) (11 members)
- Atelier (Series) (7 members)
- Atlus (Developer) (4 members)
- Atlus (Publisher) (16 members)
- Atlus USA (Publisher) (7 members)
- Atomic Elbow (Developer) (1 member)
- Audio buffer duration (Config) (7 members)
- Audio format: Automatic (Config) (1 member)
- Augmented reality (Genre) (4 members)
- Australia (Release region) (639 members)
- Autumn Games (Publisher) (2 members)