Communities related to r/whatisthisthing, with what each one is for and how it differs. Member figures come from SubMouse's safe-for-work directory.
r/whatisthisthing identifies mysterious physical objects. Specialty ID rooms and memory-find rooms are better when you already know the category—or when the thing is a half-remembered media title, not an object in hand.
Stay on whatisthisthing for unknown objects. Use whatsthisbug for arthropods, whatsthisplant for plants, and tipofmytongue for forgotten words/songs/movies.
r/whatisthisthing — For the identification of mysterious objects
For the identification of mysterious objects
TOMT: When you can't remember that…thing…
When to choose it: You half-remember a word, song, movie or similar un-googleable media.
Why it is here: Topical sibling. Public description: finding un-googleable things on the tip of your tongue.
How it differs from r/whatisthisthing: Memory/media find versus physical object ID.
Bug identification! All insects, spiders, crustaceans, etc. welcome!
When to choose it: The mystery is an insect, spider or similar arthropod.
Why it is here: Listed as related to r/whatisthisthing. Public description: bug identification for insects, spiders, crustaceans, etc.
How it differs from r/whatisthisthing: Arthropod specialist versus any object.
What's This Plant
When to choose it: You need a plant identified from photos.
Why it is here: Topical sibling. Public description: upload plant photos for identification.
How it differs from r/whatisthisthing: Plant specialist versus general objects.
Use the related subreddits finder for r/whatisthisthing: Find related to r/whatisthisthing.
Members and public descriptions come from SubMouse's safe-for-work directory (as of 2026-11-09 UTC); 7-day growth measured from 2026-11-02. Directory rank is listing order. Guide updated 2026-11-06.