The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Airtight Games (Developer) (3 members)
- Ak tronic Software & Services GmbH (Publisher) (1 member)
- Akabeisoft2 (Developer) (1 member)
- Akatsuki Works (Developer) (2 members)
- Aksys Games (Publisher) (19 members)
- Alawar Entertainment (Developer) (4 members)
- Alawar Entertainment (Publisher) (11 members)
- Alawar Stargaze (Developer) (3 members)
- Alchemist (Developer) (2 members)
- Alchemist (Publisher) (3 members)
- Aliasworlds Entertainment (Developer) (1 member)
- Alien Breed (Series) (4 members)
- Allow host gpu labels: On (Config) (1 member)
- 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)