The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Basic Editing (2 members)
- Bathynomus (5 members)
- Bean (23 members)
- BlackMamba (14 members)
- Blongus (2 members)
- Bokun (51 members)
- Braingirl (4 members)
- Braingirl:Guides (0 members)
- Braingirl:In Development (0 members)
- Braingirl:Locations (0 members)
- Braingirl Characters (1 member)
- Braingirl Guides (7 members)
- Braingirl In Development (6 members)
- Braingirl Locations (18 members)
- Braingirl Streets Hub Worlds (0 members)
- Braingirl Wiki:Guides (0 members)
- Braingirl Wiki:Images (0 members)
- Braingirl Wiki:In Development (0 members)
- Braingirl Wiki:Locations (0 members)
- Braingirl Wiki:Screenshots (0 members)
- Braingirl Wiki:Stubs (0 members)
- Braingirl Wiki:Unattributed files (0 members)
- Braingirl Wiki:Wiki skin images (0 members)
- Bralsra (2 members)
- Ca (5 members)
- Calicora (1 member)
- Candidates for deletion (194 members)
- Carson (11 members)
- Catcatcat6 (1 member)
- Cerasus (4 members)
- Cerasus Characters (20 members)
- Cerasus Collectibles (2 members)
- Cerasus Events (2 members)
- Cerasus Guides (4 members)
- Cerasus Locations (33 members)
- Character Pictures (310 members)
- Character templates (10 members)
- Characters (198 members)
- Cheo (7 members)
- Colby (6 members)
- Collectables (0 members)
- Collective Unconscious (4 members)
- Collective Unconscious Authors (61 members)
- Collective Unconscious BGM (1 member)
- Collective Unconscious Characters (2 members)
- Collective Unconscious Collectables (1 member)
- Collective Unconscious Guides (7 members)
- Collective Unconscious Locations (251 members)
- Collective Unconscious Nexus Worlds (0 members)
- Collective Unconscious Screenshots (94 members)