The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- User templates (1 member)
- Uwa (6 members)
- Uwonozoki (16 members)
- VANEGI (8 members)
- Victikirby (1 member)
- Videos (120 members)
- Vivi (3 members)
- VoxlAlien (3 members)
- WXeoWvpbbM (6 members)
- Walk Cycles (62 members)
- Wataru (183 members)
- Widdershins (2 members)
- Widgets (1 member)
- Wiki-dependent (7 members)
- Wiki icons (1 member)
- Wiki skin images (2 members)
- Wikis (20 members)
- Wooglee (2 members)
- Xen (1 member)
- YNOproject (3 members)
- YNOproject Badges (20 members)
- Yarshmellow (4 members)
- Yasakoten (7 members)
- Yeris (50 members)
- Yuki-Hitsuji (28 members)
- YumeWiki (5 members)
- Yume 2kki (12 members)
- Yume 2kki Authors (105 members)
- Yume 2kki Characters (48 members)
- Yume 2kki Collectables (22 members)
- Yume 2kki Contributors (4 members)
- Yume 2kki Effect NPCs (21 members)
- Yume 2kki Effects (2 members)
- Yume 2kki Guides (61 members)
- Yume 2kki Hub Worlds (29 members)
- Yume 2kki In Development (304 members)
- Yume 2kki Locations (1,204 members)
- Yume 2kki Locations with Wake-Up Events (59 members)
- Yume 2kki Menu Theme Previews (1 member)
- Yume 2kki Nexus Worlds (27 members)
- Yume 2kki Removed Content (3 members)
- Yume 2kki Screenshots (2 members)
- Yume 2kki Soundtrack Listings (12 members)
- Yume 2kki Timed Locations (5 members)
- Yume Nikki (12 members)
- Yume Nikki:Decorative NPCs (0 members)
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- Yume Nikki Annotated Maps (1 member)
- Yume Nikki BGM (1 member)