About r/compsci
In its own words:
Computer Science Theory and Application. We share and discuss any content that computer scientists find interesting. People from all walks of life welcome, including hackers, hobbyists, professionals, and academics.
The community was created on Mar 24, 2008, which makes it 18 years old. Since Oct 19, 2026, it has gained 550 subscribers (+0.01%). Among the 6 communities on our science list it is number 5 by size.
What sets r/compsci apart
Compared with other large communities, r/compsci leans heavily on text posts (44% of recent posts; the typical Top 100 subreddit sits at 17%). People mostly look and upvote here rather than comment — about 6.1 comments per post, against 16.2 for a typical large subreddit.
Subscriber growth
Between Sep 19, 2026 and Oct 29, 2026, r/compsci climbed from 3,994,672 to 3,996,894 subscribers (+2.2K, +0.06%). That is about 56 new members per day. The chart uses our weekly snapshots (8 so far), so it gets longer every week.
What r/compsci talks about
Across 34 recent posts (Oct 21–Oct 28), the words that come up most are “parat”, “multiplier”, “checked”, “exact” and “looking”. Other frequent themes are chains, cpu, exponential, hypothesis, false and 512-bit. Recurring phrases include “parat 512-bit”, “512-bit multiplier”, “multiplier verification” and “seconds plus”. By format, 44% are text posts, 38% are links and 9% are images.
Activity and best time to post
r/compsci gets about 5.9 new posts a day. The public archive holds 69,829 posts and 425,891 comments in total, about 6.1 comments per post. Last week the busiest day was Monday (7 posts) and the quietest was Tuesday (2). Posting peaks around 12:00 UTC and is lowest around 00:00 UTC.
Rules of r/compsci
The moderators of r/compsci list 5 rules. In short:
- Be on-topic
- No career, major, or study advice
- No homework or introductory questions
- No tech/programming support
- No purchase advice
How to join
Open reddit.com/r/compsci 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 big is r/compsci?
r/compsci has 3,996,894 subscribers, which makes it the #237 safe-for-work subreddit in the SubMouse ranking. It added 2,222 members between Sep 19, 2026 and Oct 29, 2026.
When was r/compsci created?
r/compsci was created on Mar 24, 2008, so it has been around for 18 years.
Is r/compsci still active?
Yes. r/compsci gets about 5.9 new posts a day (average of the last four weeks). Over its lifetime the archive counts 69,829 posts and 425,891 comments.
What is the best time to post in r/compsci?
Based on post counts from Oct 22, 2026 to Oct 28, 2026, the busiest day was Monday and the quietest Tuesday, and most posts arrive around 12:00 UTC, with the fewest around 00:00 UTC. More posts also means more competition, so a quieter hour can help a post get noticed.
What kind of posts are on r/compsci?
The community describes itself as: “Computer Science Theory and Application. We share and discuss any content that computer scientists find interesting. People from all walks of life welcome, including hackers, hobbyists, professionals, and academics.” Recent post titles often mention parat, multiplier, checked, exact and looking. Most posts are text posts (44%).
Is r/compsci SFW?
Yes. Reddit does not mark r/compsci as an 18+ (NSFW) community. SubMouse lists safe-for-work subreddits only.
What are the rules of r/compsci?
Join the community on Reddit first, then use “Create post”. r/compsci accepts both text and link posts, with images, galleries and polls enabled. It has 5 posted rules, starting with: “Be on-topic”; “No career, major, or study advice”; “No homework or introductory questions”. Moderators remove posts that break the rules, so read them in the sidebar before posting.
What subreddits are similar to r/compsci?
Communities with similar topics include r/theydidthemath (2.5M), r/science (34.6M), r/psychology (4.9M), r/hardware (4.4M) and r/buildapc (8.5M).
Stats from public data (data updated Oct 29, 2026; activity, rules and archive totals via the Arctic Shift archive, Oct 30, 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/compsci.