Post Ranking and Feed Mechanics
Copy-ready Claude prompt
I'm posting {{post_topic}} in r/{{subreddit}}. Given Hot rewards first-hour velocity (100+ upvotes ≈ 89% front-page odds vs. 2% for 0-5), draft a title/opener that gives a stranger scrolling New a reason to upvote in the first two sentences.Learning objectives
- Explain Hot's logarithmic weighting and ~12.5-hour decay curve.
- Define upvote velocity and the first-hour thresholds predicting front-page odds.
- Differentiate Hot, New, Rising, Top, and Controversial.
- Explain why comments and dwell time extend a post's life in Hot.
Prerequisites: Lesson 1.2.1.
Core concepts
If karma is account-level trust, ranking mechanics are post-level distribution, and they're unforgiving. Hot is logarithmic: a post's first 10 upvotes weigh as much as the next 100, which weigh as much as the next 1,000. With a ~12.5-hour decay curve, a post's fate is decided in its first hour, not its lifetime.
Upvote velocity, upvotes relative to age, is the single most important ranking signal: 50 upvotes in hour one outranks 200 accrued over 24 hours. The numbers are stark: 0-5 upvotes in hour one gives ~2% odds of reaching the front page; 100+ gives ~89%, an ~8x difference driven almost entirely by the first 60 minutes. This is also why posting time matters (Lesson 1.2.3): you need real humans awake in the minutes after you post.
The five sorts play distinct roles. New is pure chronological, every post starts here. Rising catches posts gaining upvotes at an accelerating rate, a bridge to Hot, worth watching manually to see what's about to break out. Hot is the default score+freshness balance. Top is raw score within a time window, ignoring freshness. Controversial surfaces high engagement with a near-even vote split.
Comments are themselves a ranking input: posts with active discussion stay in Hot longer than posts with equal upvotes but no comments, because dwell time is a quality signal. A post that sparks even a small real conversation in hour one outperforms an equal-score silent post, meaning the fastest way to help a post is a real comment that invites replies, not a single upvote.
Video lessons
Supporting reading
- How Reddit ranking algorithms work, Amir Salihefendic (Medium) (https://medium.com/hacking-and-gonzo/how-reddit-ranking-algorithms-work-ef111e33d0d9), canonical, code-level Hot formula.
- Reddit algorithm explained: why 94% of posts fail, Signals (https://signals.sh/blog/reddit-algorithm-explained), the first-hour probability numbers above.
- How the Reddit Ranking Algorithm Works in 2026, Fansgurus (https://fansgurus.com/blog/how-the-reddit-algorithm-works-2026), clean summary of every sort.
- clux/decay, GitHub (https://github.com/clux/decay), runnable Hot/confidence/decay code.
Exercise
Find a Rising post in a target subreddit; check back in 2-3 hours and note whether it reached Hot, with estimated first-hour velocity.
Assignment
Write 200 words explaining why an 11 PM Friday post is structurally disadvantaged vs. 9 AM Tuesday, tied to velocity and the decay window.
Claude workflow
- Skill idea: a first-hour readiness checklist reviewing a draft against velocity-friendly criteria before you submit.
- Automation: none, manufacturing early velocity via coordinated upvotes is vote manipulation, the black-hat line in Module 1.3. The only lever is a genuinely strong post at a time real humans are reading.
Expected outcomes
- Explains logarithmic Hot weighting and the ~12.5-hour decay unprompted.
- States first-hour thresholds (0-5 vs. 100+) and approximate odds correctly.
- One documented real-world Rising-post observation.