About r/AskPhysics
The community was created on Sep 8, 2011, which makes it 15 years old. Since Oct 26, 2026, it has gained 966 subscribers (+0.06%).
What sets r/AskPhysics apart
Compared with other large communities, r/AskPhysics leans heavily on text posts (85% of recent posts; the typical Top 100 subreddit sits at 34%). For its size it is unusually busy: about 24.1 new posts a day per million members, more than 80% of the Top 100. Its rhythm is strongly tied to time zones: the busiest hour (17:00 UTC) sees about 4.5× as many posts as the quietest (05:00 UTC).
Subscriber growth
Between Sep 19, 2026 and Nov 2, 2026, r/AskPhysics climbed from 1,568,713 to 1,575,579 subscribers (+6.9K, +0.44%). That is about 156 new members per day. The chart uses our weekly snapshots (9 so far), so it gets longer every week.
What r/AskPhysics talks about
Across 65 recent posts (Oct 31–Nov 4), the words that come up most are “light”, “physics”, “black”, “theory” and “quantum”. Other frequent themes are dilation, study, hole, existed, speed and relativity. By format, 85% are text posts and 15% are links.
Activity and best time to post
r/AskPhysics gets about 38 new posts a day. The public archive holds 192,876 posts and 1,755,112 comments in total, about 9.1 comments per post. Last week the busiest day was Thursday (55 posts) and the quietest was Saturday (21). Posting peaks around 17:00 UTC and is lowest around 05:00 UTC.
Rules of r/AskPhysics
The moderators of r/AskPhysics list 5 rules. In short:
- Irrelevance
- Rudeness
- No cheating on schoolwork, and show your own attempt
- Questions that went unanswered for a day
- No AI/LLM drivel
How to join
Open reddit.com/r/AskPhysics and press “Join”. Read the community rules in the sidebar before you post: every subreddit is run by its own volunteer moderators.
Frequently asked questions
How many subscribers does r/AskPhysics have?
r/AskPhysics has 1,575,579 subscribers, which makes it the #669 safe-for-work subreddit in the SubMouse ranking. It added 6,866 members between Sep 19, 2026 and Nov 2, 2026.
When was r/AskPhysics created?
r/AskPhysics was created on Sep 8, 2011, so it has been around for 15 years. The oldest post in the public archive is from Oct 19, 2011.
Is r/AskPhysics still active?
Yes. r/AskPhysics gets about 38 new posts a day (average of the last week). Over its lifetime the archive counts 192,876 posts and 1,755,112 comments. In a sample of 65 recent posts we counted 63 different authors.
What is the best time to post in r/AskPhysics?
Based on post counts from Oct 29, 2026 to Nov 4, 2026, the busiest day was Thursday and the quietest Saturday, and most posts arrive around 17:00 UTC, with the fewest around 05:00 UTC. More posts also means more competition, so a quieter hour can help a post get noticed.
What kind of posts are on r/AskPhysics?
The community describes itself as: “Ask Physics” Recent post titles often mention light, physics, black, theory and quantum. Most posts are text posts (85%).
Is r/AskPhysics SFW?
Yes. Reddit does not mark r/AskPhysics as an 18+ (NSFW) community. SubMouse lists safe-for-work subreddits only.
What are the rules of r/AskPhysics?
Join the community on Reddit first, then use “Create post”. r/AskPhysics accepts text posts only, with galleries enabled. It has 5 posted rules, starting with: “Irrelevance”; “Rudeness”; “No cheating on schoolwork, and show your own attempt”. Moderators remove posts that break the rules, so read them in the sidebar before posting.
What subreddits are similar to r/AskPhysics?
Communities with similar topics include r/Physics (3.3M), r/AskReddit (60M), r/science (34.6M), r/AskEconomics (1.5M) and r/AskMen (7.4M).
Stats from public data (data updated Nov 2, 2026; activity, rules and archive totals via the Arctic Shift archive, Nov 6, 2026). Point and comment counts are archive snapshots and can be lower than on Reddit today. SubMouse is an independent directory and is not affiliated with Reddit or the moderators of r/AskPhysics.