Hacker News Show HN Attention Half-Life Analysis

The median Show HN post receives only 2 points and 0 comments, and for those that gain traction, half of all lifetime engagement occurs within 7.2 hours. This data suggests that a Hacker News launch is a momentary spike in attention rather than a sustainable distribution strategy.

The Median Experience: 2 Points and Silence

The vast majority of Show HN submissions do not achieve front-page visibility. Based on a dataset of 41,301 launches from a 12-month period, the median outcome is 2 points and 0 comments.

Key statistics on launch outcomes include:

• Comment Rate: 61.7% of launches received no comments at all, and 78.9% received one or none.
• Distribution: The outcome distribution follows a power law with a sharp drop-off; the 90th percentile is only 8 points.
• High Success: Fewer than 2% of launches exceed 100 points.

The 7.2-Hour Attention Half-Life

Using comment timestamps as a proxy for attention, the analysis found that the median cumulative comment curve crosses the 50% mark at 7.2 hours. This means half of the total comments a post will ever receive are posted within the first 7.2 hours of its life.

Decay Velocity

Attention decays rapidly across all levels of success:

• 90% Threshold: 90% of all comments typically arrive by hour 26.
• Slowest Quartile: Even the slowest 25% of launches reach their halfway point by hour 18.
• The 48-Hour Cliff: For the median launch, only 4.2% of lifetime comments arrive after the first 48 hours. 71% of all launches are more than 90% finished with their engagement cycle by hour 48.

The Ranking Mechanism

The rapid decay is driven by Hacker News' ranking formula, which divides points by the age of the story raised to the power of 1.8. Because time is in the denominator with a high exponent, the algorithm ensures that new content is prioritized, effectively acting as a "conveyor belt into a furnace" that pushes older stories off the front page regardless of their popularity.

Success Does Not Extend Visibility

High-volume launches do not experience slower decay. The top decile of measurable launches (those with 268 points or more) has a median half-life of 7.6 hours, nearly identical to the 7.1-hour half-life of launches below that decile.

Even the most successful posts of the year—including major releases like Homebrew 6.0.0—follow the same decay curve. While success increases the absolute volume of engagement, it does not change the timing of when users leave the conversation.

Strategic Implications for Founders

Because the attention spike is so brief, a launch cannot serve as a primary distribution plan. While a front-page hit can provide a significant initial boost in users—one user reported increasing their count from 13,000 to 16,000 via a single submission—the long-term growth must rely on compounding distribution channels and consistent shipping.

Methodology and Limitations

This analysis was conducted by scraping 41,301 Show HN posts from June 18, 2025, to June 18, 2026, using the Algolia HN API.

Limitations include:

• Proxy Data: Comment timestamps were used as a proxy for attention because HN does not provide vote timestamps.
• Sample Size: Decay curves were only calculated for the 2,066 launches that received 10 or more comments, as the median launch has too few comments to generate a curve.
• Data Filtering: The API excludes flagged and dead posts, which may make the median statistics appear more favorable than they are in reality.