Mahjong All-Last Comeback Calculator
Instant all-last calculator for “who to ron and how much” or “how much tsumo is needed.” Enter table scores to get target-rank conditions.
Status
Calculates in your browser. No input is sent to a server.
How to use
Enter scores and seat info, then calculate. You get minimum ron/tsumo conditions for your target rank.
Notes (this tool)
- Tie scores are treated as non-overtake.
- Adjust manually for special table rules (for example kiriage mangan).
About this page
What does this tool do?
From four scores and your seat, it computes minimal winning-point conditions to reach a target rank (1–4).
Ron requirements are shown per discarder, and tsumo requirements by dealer/non-dealer context (including honba/kyotaku).
Typical use cases
- Quick confirmation when manual all-last math is hard
- Check comeback requirements during streams or live viewing
- Align target points before push/fold decisions
Recommendations (practical)
- Always include kyotaku/honba before deciding; they are easy to forget
- Check per-discarder rows because ron requirements vary by who deals in
- Tie handling differs by ruleset, so confirm final tie behavior with your table rules
What this tool does
- Show current rank and required gap to target rank
- Show minimal ron requirement per discarder
- Show minimal tsumo requirement (dealer/non-dealer)
Notes
- Uses common riichi scoring tables; apply local special-rule adjustments separately.
- Tie scores are treated conservatively as non-overtake results.
- Output is a practical estimate; reconfirm stick counts and continuation conditions in real play.
Debugging workflow (recommended)
- Enter four scores and your seat/dealer seat
- Set honba, kyotaku, and target rank
- Read ron/tsumo rows and pick the minimum feasible condition
Referenced specs
- Common riichi scoring conversion (han/fu to payments)
- Honba handling (ron +300 / tsumo +100 each payer)
- Kyotaku handling (+1,000 to winner per stick)
FAQ
Why do ron requirements differ by discarder?
Because only the discarder loses points on ron, final standings depend on who deals in.
How are dealer/non-dealer tsumo requirements derived?
The tool enumerates standard han/fu-based payment candidates and picks the minimum that reaches your target rank.
References
Next to view (diagnostic order)
These links are generated from site_map rules in recommended diagnostic order.
- Mahjong Point Calculator — Calculate point movement on win from han/fu, honba, and kyotaku
- Unix Time Converter — Convert Unix seconds/milliseconds and date-time both ways
- Cron Builder — Build 5-field cron and preview upcoming runs
- Text Counter — Count characters including newline and full/half-width views
- Regex Tester — Test regex matching, extraction, and replacement
- Regex Cheat Generator — Generate regex patterns from practical templates
- SQL WHERE Builder — Build WHERE clauses and bind params from condition rows
- SQL UPSERT Builder — Generate dialect-specific UPSERT SQL and bind values
Same-theme links
Quick Calculators
One-screen calculators for commonly forgotten quick math
- Mahjong Point Calculator — Calculate point movement on win from han/fu, honba, and kyotaku
- Unix Time Converter — Convert Unix seconds/milliseconds and date-time both ways
- Cron Builder — Build 5-field cron and preview upcoming runs
- Text Counter — Count characters including newline and full/half-width views
- Regex Tester — Test regex matching, extraction, and replacement
- Regex Cheat Generator — Generate regex patterns from practical templates
- SQL WHERE Builder — Build WHERE clauses and bind params from condition rows
- SQL UPSERT Builder — Generate dialect-specific UPSERT SQL and bind values
- Random Token Generator — Generate random tokens with selectable byte size and encoding
Example
Target: Rank 2 South seat: 24,100 / dealer: East / honba: 1 / kyotaku: 1 Result: Reach rank 2 by ron 5,200 from West (5,500 incl. honba)