About r/slatestarcodex
Slate Star Codex was the former name for a blog by Scott Alexander about human cognition, politics, and medicine. In 2021, the name was changed to Astral Codex Ten: https://astralcodexten.substack.com/
The community at a glance
r/slatestarcodex is a Subreddit for Longevity Enthusiasts and Biohackers with roughly 83K members. It uses a forum format for communication. It is the 4th largest community in the Biohacking topic page and the 10th largest community in the Longevity topic page.
Roughly 10K members have joined in the past year. Popular discussion topics include Looking For, Ai, and Worst. Product recommendations often mention book.
Community Topics
Community Features
This community has a forum
Subreddit Analysis
via GummySearchMember growth over time
All time (yearly)
- 2015: 1K members
- 2016: 2K members
- 2017: 4K members
- 2018: 6K members
- 2019: 10K members
- 2021: 22K members
- 2023: 14K members
- 2024: 7K members
- 2025: 8K members
- 2026: 7K members
Past year (monthly)
- Sep: 438 members
- Oct: 514 members
- Nov: 607 members
- Dec: 969 members
- Jan: 848 members
- Feb: 679 members
- Mar: 821 members
- Apr: 870 members
- May: 2K members
- Jun: 867 members
- Jul: 1K members
- Aug: 464 members
Topics
- Looking For36 posts in the past month#136Looking For
- Ai36 posts in the past month#236Ai
- Worst11 posts in the past month#311Worst
- Philosophy9 posts in the past month#49Philosophy
- Technology8 posts in the past month#58Technology
Flair
- AI20 posts in the past month
- OpenAI agents rebuilt a secret message board after the company shut it down
- OAI engineers discuss the details of the HF Incident at the Black Hat conference
- FelonyBench The most important New Benchmark for AI
#120AIOpenAI agents rebuilt a secret message board after the company shut it down · OAI engineers discuss the details of the HF Incident at the Black Hat conference · FelonyBench The most important New Benchmark for AI - Existential Risk6 posts in the past month
- No One Believes a True Believer
- "Plz Don’t Kill Us: Inside AI safety’s influencer bootcamp; Can TikTokers make existential risk mainstream?", Celia Ford (2026-08-04)
- Q2.5 2026 Timelines Update: Uplift and Revenue
#26Existential RiskNo One Believes a True Believer · "Plz Don’t Kill Us: Inside AI safety’s influencer bootcamp; Can TikTokers make existential risk mainstream?", Celia Ford (2026-08-04) · Q2.5 2026 Timelines Update: Uplift and Revenue - Medicine3 posts in the past month
- Why is assisted dying so rare, even where it's legal?
- Black Wednesday
- Lumina again
#33MedicineWhy is assisted dying so rare, even where it's legal? · Black Wednesday · Lumina again - Rationality3 posts in the past month
- How Much Do You Value Online Anonymity?
- The Case Against Kanji
- Reading recommendations on double cruxing?
#43RationalityHow Much Do You Value Online Anonymity? · The Case Against Kanji · Reading recommendations on double cruxing? - Politics2 posts in the past month
- "Why I Left Google DeepMind", Turntrout
- An analysis about the left vs right division being a false dialectic, that gets deployed to distract the population while conveniently leaving capital intact?
#52Politics"Why I Left Google DeepMind", Turntrout · An analysis about the left vs right division being a false dialectic, that gets deployed to distract the population while conveniently leaving capital intact?
Product recommendations
- book13 posts in the past month
- Best book on Bayesian thinking
- What are the best 1-3 books I can read to be able to learn to spot, point out and name fallacies, illogical and magical thinking, evasion tactics, rhetoric, et cetera?
- Best non-fiction book(s) you have read this year?
#113bookBest book on Bayesian thinking · What are the best 1-3 books I can read to be able to learn to spot, point out and name fallacies, illogical and magical thinking, evasion tactics, rhetoric, et cetera? · Best non-fiction book(s) you have read this year?
Community Reviews
Frequently asked questions
- Who is r/slatestarcodex for?
- Best for Longevity Enthusiasts and Biohackers enthusiasts looking for a Reddit-based community with forum discussion.
- Is r/slatestarcodex free to join?
- This listing is not marked as paid-only. Access rules and any fees are decided by the community.
- How many members does r/slatestarcodex have?
- Roughly 83K members, based on figures reported by the community or its host. Member counts are approximate and change over time.
- What platform is r/slatestarcodex on?
- r/slatestarcodex runs on Reddit. Reddit communities (or "subreddits") are forum-based groups on the popular social news aggregation, web content rating, and discussion website Reddit. Reddit is commonly known as "the front page of the internet". Users submit content to the site such as links, text posts, and images, which are then voted up or down and discussed by other members. From investing Reddit communities, to professional ones, to ones just for laughs, you're likely to find a community for you on Reddit.
- What topics does r/slatestarcodex cover?
- On the Hive Index, r/slatestarcodex is organized under Longevity Enthusiasts, Biohackers.
- How do I join r/slatestarcodex?
- You can join r/slatestarcodex by clicking this link, or pressing the "Go to community" button above.
- What are the Longevity communities like?
- Communities for people interested in extending healthspan and lifespan through science-backed interventions. You will find research-focused forums, protocol-follower communities on Skool, and spaces around metabolic health monitoring and the latest biotech developments in the longevity field.
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