TLDR
If you’re posting Show HN within 24 hours of finishing a Product Hunt launch, the practical recommendation is 9–10 AM US Eastern time, Monday through Thursday. That window matches the early part of the US workday, gives the post 6+ hours to accumulate points before US Pacific time wakes up, and aligns with the time-decay shape baked into HN’s ranking formula S-003 S-004.
Late-afternoon or weekend submissions tend to die on rank 30+ before anyone sees them — not because HN penalizes the time, but because the algorithm’s age decay outruns the post’s vote-accrual curve when fewer eyeballs are online.
Why the problem happens
HN’s submission and ranking guidelines describe a system where each submission’s rank decays over time, balanced against the votes it accrues S-004. The official Show HN page reinforces the format (build something, share it, ask for feedback) but doesn’t specify a posting time S-003.
That gap — algorithm public, optimal-time-of-day not public — is where the founder community fills in. Long-running founder writeups from Pieter Levels, Tony Dinh, and others document the early-US-morning window as the consistently best slot for indie launches S-016 S-017. The mechanism is simple: more eyeballs are online → faster initial vote accrual → the post crosses the decay threshold before fading.
This isn’t a “hack”. It’s a consequence of the algorithm. Submit at 4 PM ET on a Friday and you’re competing against late-Friday submissions for a smaller weekend audience, with the same time decay running against you.
The 9 AM ET timing rule
Here’s the rule, distilled:
| Day of week | Best window (ET) | Why |
|---|---|---|
| Monday | 9–10 AM | Highest weekday Show HN volume + most active commenters |
| Tuesday | 9–10 AM | Same as Monday; slightly less new-product noise |
| Wednesday | 9–10 AM | Mid-week peak, often the highest single-day rank |
| Thursday | 9–10 AM | Last solid weekday window |
| Friday | Skip | EU lunch / US early-morning collision + low weekend follow-through |
| Saturday | Skip | Weekend HN audience is smaller and slower to engage |
| Sunday | 9–10 AM (only if Monday is blocked) | Sunday Show HN gets carry-over Monday traffic |
The window is a band, not a precise minute. 9:00, 9:15, 9:42 — all roughly equivalent. What matters is being inside the 9–10 AM ET band on a Monday–Thursday.
Step-by-step: how to time your Show HN after PH
- Don’t post both on the same day. PH and HN are different audiences and the two launches compete for your founder bandwidth. Let PH have its 24-hour window first.
- Wait until the PH window closes (usually midnight Pacific). At that point, you have a known PH upvote count to reference in your Show HN body — even if you don’t include the number, you have language for it.
- Pick the next weekday at 9–10 AM ET. If PH closed Tuesday morning Pacific, that’s Wednesday at 9 AM ET. If it closed Friday, wait until Monday.
- Write the title. Two formats work:
- Question: “Show HN: I built X — what would you change?”
- Specific claim: “Show HN: A 12-row post-launch recovery scorecard”
- Avoid “Show HN: My new app for X” — generic titles get bypassed.
- Post. Do not edit the title after submission. HN sometimes auto-edits to enforce the “Show HN: ” prefix; that’s fine.
- Stay in the thread for the first hour. Reply to every comment within 10 minutes. Engagement signals matter for rank.
- Do not ask for votes anywhere. HN’s submission guidelines explicitly prohibit vote manipulation S-004. Even a single tweet asking for upvotes can get the post flagged.
Concrete example
Founder finishes a Product Hunt launch on Tuesday afternoon Pacific time. The PH window closes Wednesday at midnight Pacific.
- Wrong: post Show HN at 8 PM PT Wednesday with title “Show HN: My SaaS for launch recovery”. Post submitted; rank is 22 within 90 minutes; dies at rank 30 by Thursday morning.
- Right: post Show HN at 9:20 AM ET Thursday with title “Show HN: A 12-row scorecard for the 7 days after a Product Hunt launch”. Post hits rank 8 within 90 minutes, peaks at rank 4, accumulates 180 points and 60+ comments over 14 hours.
The difference is mechanical. The Thursday-morning post gets ~8 hours of high-eyeballs accumulation before West-Coast lunch, by which point its point-to-age ratio is high enough to survive the decay curve.
Visual — when posts die
Rank ↑
1 │ ●● ← Thursday 9:20 AM ET post peaks rank 4
5 │ ●● ●●●
10 │ ●● ●●●
15 │ ●● ●●●●
20 │ ●●●●●
25 │ ○○○ ●●●●●● ← still alive at 16 hours
30 │ ○○○○ ← Wednesday 8 PM PT post dies here
└────────────────────────────────→ time (hours)
0 2 4 6 8 10 12 14Same product, same body, same submitter. The only variable is the posting hour. Stylized — not measured — but it matches the pattern repeated in founder writeups S-016 S-017.
Common mistakes
| Mistake | Why it happens | What to do instead |
|---|---|---|
| Submitting at 4 PM ET | Founder finishes coding the launch page at 3 PM, hits submit | Wait until 9 AM ET the next weekday |
| Submitting on Friday or Saturday | Founder wants the launch “done” before the weekend | Hold until Monday morning |
| Reposting if the first attempt died | Founder thinks the title was wrong | Don’t repost — HN treats reposts as duplicates. Wait 60–90 days minimum |
| Asking for upvotes on Twitter | Feels like activation | HN guidelines prohibit vote solicitation S-004 |
| Skipping Show HN because PH “went well” | Resource constraint | Show HN audience is different — usually higher-converting for B2B/dev tools |
| Editing the title 10 minutes after submission | Founder spots a typo | Editing resets some engagement signals — accept the typo |
FAQ
What if I’m not in US Eastern time? Set a calendar reminder. The audience is in US time zones; your local time doesn’t matter.
Does HN really penalize late-afternoon posts? Not explicitly — the official guidelines do not list a “posting time” rule S-004. The effect is indirect: fewer eyeballs online → slower vote accrual → the time-decay component of the ranking formula outruns you.
What if my product is for a non-US audience? Show HN is a US-centric audience regardless. If your product targets, say, EU compliance officers, Show HN may still not be the right channel — consider EU-specific communities instead.
Can I post Launch HN instead? Launch HN is for YC-backed companies S-003. If you’re not in YC, Show HN is the right surface.
My title got modified by mods. Is that bad? No. HN moderators sometimes adjust titles for clarity or guideline compliance. A moderator edit usually doesn’t hurt rank.
Next steps
If you launched on PH yesterday and you’re reading this, the answer is simple: tomorrow morning at 9:15 AM ET. While you wait, run the Post-launch 7-day recovery scorecard on the homepage. The Show HN row is one of the 12 — make sure it’s checked tomorrow morning. Then read the Product Hunt launch with no signups — what to do next week decision tree for the rest of the week.