The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- If (3 members)
- If Characters (1 member)
- If Guides (3 members)
- If Locations (52 members)
- If Nexus Worlds (10 members)
- If Screenshots (112 members)
- Image license templates (12 members)
- Images (798 members)
- Immuno (3 members)
- Imported vocabulary (8 members)
- In Development (763 members)
- Infobox templates (12 members)
- Infoboxes with missing header styling (82 members)
- JIVV (10 members)
- Jaies (1 member)
- Jared (6 members)
- Jekyle (8 members)
- Jetrotal (1 member)
- Jitensha (3 members)
- John Ruiz (3 members)
- Jojogape (5 members)
- Joo (1 member)
- Juda (24 members)
- K0OdntepKs (2 members)
- KKO (1 member)
- Kaite20 (0 members)
- Kappa (62 members)
- Konaki (4 members)
- Kong (15 members)
- Kontentsu (275 members)
- Kubotsuki's Nexus Worlds (0 members)
- Kubotsuki's Worlds (79 members)
- Kubotsuki BGM (1 member)
- Kubotsuki Screenshots (1 member)
- Kuraud (95 members)
- Kurokagi (18 members)
- Kuroku (33 members)
- LSD (37 members)
- Lakes (1 member)
- Led (2 members)
- Lemniscate (25 members)
- Light (27 members)
- Location templates (7 members)
- Locations (3,364 members)
- Locations with Wake-Up Events (3 members)
- Luok (5 members)
- Lysenthe (2 members)
- MM1920 (4 members)
- MadameMimic (8 members)
- Madotsuki images (93 members)