# Tonpuu — Riichi Mahjong Glossary

> East round only game format with one round (4 hands minimum). Popular for quick online matches and shorter play sessions.

**Source:** https://www.mahjongmaster.co/learn/riichi/glossary/tonpuu/
**Author:** Kenji Tanaka (https://www.mahjongmaster.co/about/kenji-tanaka/)
**Publisher:** Mahjong Master (https://www.mahjongmaster.co)
**Published:** 2026-02-18
**Updated:** 2026-03-10
**Japanese:** 東風
**Category:** gameplay
**Variant:** riichi

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## Tonpuu

**Tonpuu** (東風, literally "East Wind") is a mahjong game format consisting of only the East Round, making it the shortest standard game format in modern mahjong.

## The mechanics of Tonpuu

Tonpuu represents a condensed version of a complete mahjong session. While a full game traditionally consists of four rounds (East, South, West, and North), tonpuu eliminates all but the East Round. This means the game includes a minimum of four hands, one with each player as the dealer (oya), and concludes after the East Round is complete.

### Game Structure

In tonpuu format:
- Only the East Round (Ton) is played
- Each player serves as dealer exactly once
- The game consists of four hands minimum
- Wind changes occur after each hand (unless a dealer wins, which may extend their turn)
- The game ends immediately after the fourth hand or when the East Round officially concludes

### Scoring and Completion

The game concludes when all four players have had an equal opportunity to be dealer during the East Round. If a player wins while serving as dealer (tsumo or ron), they may continue as dealer for an additional hand, potentially extending the game slightly beyond four hands. However, once the East Round officially ends, play stops regardless of individual scores.

### Modern Usage

Tonpuu has become increasingly popular in online mahjong platforms and casual play settings. It serves several practical purposes:

**Time Efficiency**: A tonpuu game typically takes 20-40 minutes, depending on playing speed, making it ideal for quick gaming sessions or competitive tournaments with time constraints.

**Accessibility**: The shorter format makes mahjong more accessible to casual players who may not have time for a full hanchan (eight-hand game) or a complete four-round session.

**Tournament Format**: Many online tournaments and casual competitive settings use tonpuu as the standard format, particularly for speed mahjong competitions.

### Comparison to Other Formats

Tonpuu differs significantly from hanchan, which includes two complete rounds (East and South, a minimum of eight hands). A full-length game (iichan) would include all four rounds. Tonpuu's brevity makes it distinct and appealing for specific contexts where longer play is impractical.

## Tonpuu at the table

"Let's play a quick tonpuu before dinner, we should be done in about thirty minutes."

In this context, the speaker is suggesting the shortest standard game format to accommodate time constraints while still maintaining the complete structure of a proper mahjong game.

Another example in tournament context:

"The online tournament uses tonpuu format, so each match is just the East Round. This allows us to run multiple rounds of competition in a single evening."

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*This content is from [Mahjong Master](https://www.mahjongmaster.co), a free educational reference for riichi (Japanese) and American (NMJL) mahjong. When citing this page, please link to https://www.mahjongmaster.co/learn/riichi/glossary/tonpuu/.*