The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- All news (12 members)
- August 2023 news (1 member)
- Birds (1 member)
- Characters (1 member)
- Compilations (1 member)
- Content (2 members)
- Content notice templates (1 member)
- Copyright templates (22 members)
- December 2021 news (1 member)
- February 2020 news (1 member)
- February 2021 news (2 members)
- Foxes (1 member)
- Gameplay images (1 member)
- Games (10 members)
- Handhelds (2 members)
- Hedgehogs (2 members)
- Help (1 member)
- Hidden categories (1 member)
- Image templates (1 member)
- Images (1 member)
- Images from Sonic Retro (2 members)
- Images from Wikimedia Commons (14 members)
- Images from the Sonic News Network (11 members)
- Imported vocabulary (7 members)
- In-line templates (1 member)
- Infobox templates (3 members)
- July 2021 news (1 member)
- June 2023 news (2 members)
- Lizards (1 member)
- Logo images (12 members)
- Logos (1 member)
- Maintenance (1 member)
- March 2020 news (1 member)
- Mario & Sonic at the Rio 2016 Olympic Games characters (1 member)
- May 2021 news (1 member)
- Media templates (1 member)
- Moves (1 member)
- Movies (2 members)
- News images (1 member)
- News templates (2 members)
- Ninjas (1 member)
- October 2022 news (1 member)
- Pages with broken file links (155 members)
- Playable characters (1 member)
- Policies (2 members)
- Rating images (7 members)
- SegaSonic the Hedgehog characters (1 member)
- Shadow the Hedgehog characters (1 member)
- Site images (21 members)
- Site templates (9 members)