Board Games 🇬🇧United Kingdom19th century

Reversi / Othello

Officially Othello (trademarked) / Reversi (public domain original)

Abstract strategy game invented 1883 in England — 2 players place black/white discs on 8×8 board; flanking opponent's discs converts them to your color. Simple rules ('A minute to learn... a lifetime to master'); huge in Japan; WOF World Othello Championship since 1977; computer-solved for perfect draw (2023).

📐8×8 board (typically green)⏱~20 min🌤indoor

What is Reversi / Othello?

Reversi/Othello is a 2-player abstract strategy board game with one of the shortest rule-books + deepest strategic depth in board gaming. HISTORY: Original REVERSI invented independently by two Englishmen — Lewis Waterman + John W. Mollett — around 1883; commercial success 1888 (Jaques of London). Fell into obscurity ~1900. REINVENTED 1971 by Japanese salesman GORO HASEGAWA who added new starting position + trademark name 'OTHELLO' (from Shakespeare's play featuring Black + White characters). Marketed by Tsukuda Original in Japan 1973; global success. Modern OTHELLO = trademarked Hasegawa version; REVERSI = older public-domain original. Slight rule differences (starting position). GAMEPLAY: 8×8 board; each player has 64 identical discs (one side black, one white). Starting position: 4 discs in center in diagonal pattern (2 black + 2 white). Black moves first. Each move: (1) Place your disc on empty square. (2) Must FLANK opponent's disc(s) between your placed disc + another of your discs (in any of 8 directions: horizontal, vertical, diagonal). (3) All flanked opponent discs FLIP to your color. If no legal flanking move, player passes; if neither player can move, game ends. If board full, game ends. WIN = most discs of your color when game ends. SCORE: total discs on board (max 64). STRATEGY DEPTH: mobility (available moves), corner control (corners never flipped), edge control, tempo, parity (odd/even move calculation). Slogan: 'A minute to learn... a lifetime to master.' COMPUTER-SOLVED: Perfect play from both sides = DRAW (proven late 2023 by Hiroki Takizawa + others). WOF (World Othello Federation) governs since 1977; annual WORLD OTHELLO CHAMPIONSHIP + national federations. JAPAN dominant nation (Reversi/Othello #1 abstract board game there). Notable champions: Hideshi Tamenori (Japan, 8x World Champion — GOAT), Ben Seeley (USA), Piyanat 'Cassy' Aunchulee (Thailand). Ratings system similar to chess; grandmaster titles. Estimated 100+ million people have played casually; competitive community small but intense.

Quick facts

How it works

Objective

Have the most discs of your color on the board when neither player can move.

Match structure

Single-game or best-of-N in tournaments. World Championship: Swiss-round pairings then knockout finals.

Rules

Basic rules

8×8 board, 64 discs
Standard board; each disc has black on one face + white on other.
Fixed starting position (Othello)
4 discs placed in center 2×2 square in diagonal pattern: 2 black at top-right + bottom-left, 2 white at top-left + bottom-right.
Black moves first
Player with black discs makes the first move. Alternating turns thereafter.
Placement must flank
Place disc on empty square such that it FLANKS one or more of opponent's discs (in a straight line — horizontal, vertical, or diagonal) between your new disc + another of your discs already on board.
Flanked discs flip
All opponent's discs caught between your two discs are flipped to your color. Multiple directions can flip in single move.
Must move if possible
If you have any legal move, you must play it. Cannot pass voluntarily.
Pass if no legal move
If no legal move available, you pass; opponent continues moving until they also can't move.
Game ends
When both players can't move (or board full). WINNER = player with MOST DISCS of their color on board. Tie = draw.

Advanced rules

Reversi vs Othello starting position
Reversi: players place first 4 discs freely (subject to constraints). Othello: fixed diagonal starting position. Minor difference but affects early game.
Mobility principle
Having more legal moves than opponent = strategic advantage. Restricting opponent's options is often more valuable than maximizing your own disc count.
Corner control
Corners (4 squares at corners of board) can NEVER be flipped once placed. Highly valuable strategic anchors.
X-squares + C-squares (dangerous)
X-squares (diagonally adjacent to corners) + C-squares (orthogonally adjacent to corners) often GIVE UP corners to opponent. Avoid unless strategic.
Edge play
Edges harder to flip (only 1 direction of flanking possible). Building stable edge groups is key mid-game strategy.
Parity (odd/even move count)
Endgame technique: count remaining moves; forcing opponent to move first in critical region ('wipeout' or 'tempo' plays).
Wipeout / 'sweep'
Rare but possible: opponent has no discs at end. Awarded 64-0 in tournament scoring.
Opening theory (databases)
Named openings: Tiger, Chicago, Perpendicular, Diagonal, Perpendicular Rose, F5 (universal first move — flanks D4). WThor database catalogs 100,000+ pro games.
Tournament time controls
WOF standard: 30 min per player per game. Blitz: 5 min per player.
Draw = 32-32 disc split
Perfect play by both sides = draw (proven by computer 2023). Draws common between top players.

Scoring

Count discs at game end. Most discs = winner. Tournament scoring often uses disc differential (winning by 40-24 scores 40-24).

Action	Points
Discs at game end	Sum of all discs of your color
Game win	1 pt + disc differential for tie-break
Draw (32-32 or equal)	0.5 pt each
Wipeout (opponent 0 discs)	1 win + 64-0 differential
Tournament (Swiss + knockout)	Match wins + disc differential

Win condition · Have the most discs of your color when the game ends (neither player can move OR board full).

Playing area

Called

8×8 board (typically green)

Dimensions

64 squares (8×8); usually green board with grid. Tournament boards ~30×30 cm.

Standard 8×8 board. Discs black on one face + white on other. Reversi = starting position can be chosen; Othello = fixed diagonal starting position (2 black + 2 white in center).

Equipment

Othello/Reversi board
8×8 grid; typically green felt or plastic. $5-30.
64 discs (black/white)
Reversible discs; place with your color up. Plastic in most sets; wooden or bakelite for premium sets.
Optional chess-style clock
Tournament play often uses 25-min per side clocks.

Officiating

WOF (World Othello Federation) governs international rules + championship. National federations (Japan Othello Federation, French Federation, etc.) organize local events.

Tournament director
Head arbiter (for major events)
Round officials for pairings + timing

Strategies

Learn 3-4 opening lines
F5 first move standard; study Tiger, Chicago, Perpendicular responses. WOThello + iOthello apps have free databases.
Prioritize mobility over disc count
Common beginner mistake: flip max discs each move. Better strategy: flip FEW discs early to restrict opponent's options.
Avoid X-squares + C-squares (dangerous)
Squares diagonal/adjacent to corners often give up corners. Only play there when strategically justified.
Control corners
Corners never flip; foundation of edge stability. Late-game corner captures decisive.
Endgame calculation
Last 10-15 moves fully analyzable; count discs + parity to secure victory.
Play online (eOthello, Playok, iOthello)
Free online play against rated opponents; get feedback via post-game analysis.
Study Tamenori's games
WThor + WOF databases have 100,000+ pro games. Studying GOAT games teaches strategic principles.
Practice endgame puzzles
Endgame puzzles (last 10-20 moves) develop calculation. FForum + iOthello have puzzle sets.
Play in WOF-rated tournaments
Online + in-person WOF-rated events provide official rating + Grandmaster path.
Attend local Othello club
Small but active clubs in most major cities. Japan Federation has strongest infrastructure.

Terminology

Reversi: Original 1883 version; public domain name.
Othello: 1971 Hasegawa version; trademarked; identical rules but fixed starting position.
Disc / Piece: Reversible black/white marker used in game.
Flank: Sandwich opponent's discs between two of your own; triggers flip.
Flip: Change opponent's disc to your color via flanking.
Corner: 4 corner squares; NEVER flipped once placed; strategic gold.
X-square: Diagonally adjacent to corner (b2, b7, g2, g7); dangerous — often gives corner to opponent.
C-square: Orthogonally adjacent to corner (a2/b1/a7/b8/etc.); also dangerous.
Edge: Non-corner squares on outer ring of board.
Mobility: Number of legal moves available; strategic advantage to have MORE than opponent.
Parity: Odd/even count of remaining moves; endgame calculation tool.
Tempo: Turn initiative; can be gained/lost via mobility restriction.
F5 opening: Universal first move (Black plays F5 flanking D4).
Wipeout: Winning with opponent having 0 discs (rare but possible).
Draw / 32-32: Tie game; perfect play = draw (proven 2023).
Meijin: 'Master' — Japan's most prestigious Othello title.
WOF: World Othello Federation.
WThor: Database of 100,000+ pro games; standard research tool.
FForum / FFO: French Othello Federation forum + database resources.
Anti-Othello: Reverse-goal variant — FEWEST discs wins.

Major competitions

World Othello Championship (WOC)
annual · worldwide (rotating hosts) · since 1977
European Othello Championship
annual · Europe · since 1979
Japan Othello Championship (Meijin)
annual · Japan (most prestigious national title) · since 1974
Team World Championship
biennial · worldwide (national teams) · since 1990
Online Othello leagues (WOF + WOThello)
ongoing · worldwide online · since 2000

Where it is played

Governing bodies

World Othello Federation (WOF)
Founded 1977 · worldwide (rotating leadership)
Official site ↗
Japan Othello Federation
Founded 1973 · Tokyo, Japan
French Othello Federation (FFO)
Founded 1980 · France
US Othello Association (USOA)
Founded 1980 · USA
Othello UK Federation
Founded 1976 · UK

Famous names & records

Famous athletes

Hideshi Tamenori (Japan) — 8× World Othello Champion; GOAT of Othello
Kunihiko Tanida (Japan) — 3× World Champion; legendary early era
Ben Seeley (USA) — 1993 World Champion; long-tenured competitor
Takuji Kashiwabara (France, Japanese-born) — 2× World Champion; renowned analyst
Piyanat 'Cassy' Aunchulee (Thailand) — Multi-time World Championship finalist
Emmanuel Caspard (France) — 2007 World Champion
Yusuke Takanashi (Japan) — Modern top competitor
Vasu Patil (India/USA) — Rising modern competitor
Kazuki Okamoto (Japan) — 2019 World Champion
Naoki Wada (Japan) — Multi-time Japan Meijin

Records

Original Reversi invention
Waterman + Mollett — ~1883 England; commercial 1888 Jaques of London (1883)
Othello reinvention + trademark
Goro Hasegawa — 1971 Japan; commercial 1973 Tsukuda Original (1971)
First World Othello Championship
WOF — 1977 Tokyo, Japan (1977)
Most World Championship titles
Hideshi Tamenori (Japan) — 8 titles across 1990s-2000s (2010)
Game solved (perfect play = draw)
Hiroki Takizawa + team — Computer-proved November 2023 (2023)
Longest continuous WOC held
WOF — 45+ consecutive years since 1977 (2024)

Learn this sport

beginner

1
Learn rules (5 min)
Board setup + placement + flanking + game end. Rules genuinely fit on 1 page.
2
Play 10-20 casual games
Any online site (Playok.com free) or physical set. Get feel for flipping.
3
Watch beginner videos (YouTube)
Search 'Othello beginner strategy' — 30 min videos teach mobility + corner concepts.

intermediate

1
Study 5-10 named openings
F5-D6-C4 etc. named openings in WOThello or iOthello. 200-500 games to internalize.
2
Join online rated ladder (eOthello)
eOthello.com or Playok rated system; climb 1200 → 1800 rating.
3
Endgame puzzle practice
iOthello has puzzle mode; solve 10-20 min daily improves calculation.

advanced

1
WOF-rated tournament entry
Online + in-person WOF events; get official rating + climb ranks.
2
Meijin / National Championship path
Japan's Meijin is highest national prestige. National federations run own championships.
3
World Othello Championship qualification
Top national + open qualifier players compete annually; 30-50 players from ~20 countries.

Frequently asked

What is the difference between Reversi and Othello?+

SAME GAME with tiny differences. REVERSI = original 1883 English game by Waterman + Mollett; public domain name. OTHELLO = 1971 Japanese reinvention by Goro Hasegawa; TRADEMARKED brand (Mattel now owns Othello trademark in USA/Europe). RULE DIFFERENCES: (1) STARTING POSITION — Reversi lets players place first 4 discs freely (with constraints); Othello uses FIXED starting position (2 black + 2 white in center diagonal pattern). (2) Otherwise IDENTICAL rules: 8×8 board, flank + flip, most discs win. Modern competitive play universally uses OTHELLO rules (fixed start). Casual players might use either term. WOF (World Othello Federation) uses Othello brand. Historically Reversi came first (1883); Othello was strategic reinvention (1971) that popularized the game globally.

How do you win at Othello / Reversi?+

GAME ENDS when neither player can make a legal move (typically when board is full at 64 discs, but can end earlier if both players stuck). WINNER = player with MOST DISCS of their color on board. Ties are DRAWS (32-32 split). SCORING beyond just win/loss: (1) Casual: just win/loss. (2) Tournament: disc DIFFERENTIAL matters as tiebreak (winning 40-24 better than 33-31). (3) WIPEOUT = winning with opponent at 0 discs = considered maximum score (64-0). PERFECT PLAY = DRAW: computer-proved November 2023 by Hiroki Takizawa + team that both sides playing perfectly leads to a 32-32 tie. This makes Othello a SOLVED GAME (like checkers, connect four). But human play far from perfect — huge strategic depth remains.

What is the best strategy for beginners?+

COUNTER-INTUITIVE #1 TIP: DON'T MAXIMIZE FLIPS. Beginners flip max discs each move; experts flip FEW discs early to restrict opponent's options. WHY: opponent needs open squares next to your discs to move; if you're the only color visible in an area, opponent has fewer moves = FORCED into bad squares. STRATEGIC PRIORITIES: (1) MOBILITY — always have MORE legal moves than opponent. (2) CORNER CONTROL — corners NEVER flip; make them yours. (3) AVOID X-SQUARES — squares diagonal to corners (b2, b7, g2, g7) OFTEN GIVE CORNERS to opponent. Rare exceptions apply. (4) EDGE STABILITY — build stable edge groups mid-game. (5) ENDGAME PARITY — count remaining moves in each region; force opponent to move first in critical areas. STANDARD OPENING: F5 (Black's universal first move) → D6 (White's most common response). Watch YouTube tutorials from Ben Seeley, Kashiwabara, or WOF channel for visual explanation.

Is Othello a solved game?+

YES — SOLVED as a DRAW in November 2023 by Japanese researcher Hiroki Takizawa + team. Computer proof shows both sides playing perfectly leads to 32-32 tie. WHAT SOLVED MEANS: computer can determine best move at every position + guarantee at least draw against any opponent. Similar to checkers (solved 2007, draw) + connect four (solved 1988, first player wins). CHESS + GO are NOT solved due to complexity. IMPLICATIONS FOR HUMANS: (1) HUMAN PLAY still far from perfect — even top pros make mistakes. (2) STRATEGIC DEPTH remains — thousands of playable positions per game. (3) COMPETITIVE PLAY continues normally — humans can't compute perfect play in real time. (4) COMPUTER OTHELLO PROGRAMS now unbeatable by humans (like chess engines). (5) OPENING THEORY complete — top programs know all key opening lines. Solving didn't kill the game; it clarified that CORE STRATEGY (mobility, corners, edges) is CORRECT. Amateur + tournament play remains vibrant.

Is Othello popular?+

MODERATELY popular globally, HUGELY popular in Japan. STATS: (1) ~100 MILLION+ have played casually worldwide. (2) COMPETITIVE community small — ~5,000 rated tournament players globally. (3) JAPAN #1 abstract board game after chess/shogi — millions of casual + tournament players. (4) 30-50 countries have national federations. (5) Annual World Championship draws 40-80 competitors from 15-25 countries. WHY POPULAR: (1) EASY TO LEARN (5-min rules). (2) DEEP STRATEGY ('a lifetime to master'). (3) FAST GAMES (10-20 min casual). (4) PORTABLE (small board + reversible discs). (5) STRONG ONLINE PLATFORMS (Playok, eOthello, iOthello). WHY NOT MORE POPULAR: (1) LESS PRESTIGE than chess/go. (2) SMALLER TOURNAMENT PRIZES. (3) NO PROFESSIONAL LEAGUE. (4) COMPETES with hundreds of modern board games. Still one of top 10 abstract strategy games worldwide + top 3 in Japan.

Who is the greatest Othello player of all time?+

HIDESHI TAMENORI (Japan) is universal GOAT. RESUME: 8× WORLD OTHELLO CHAMPIONSHIP TITLES (1990s-2000s) — no one else has more than 3. Legendary for opening theory + endgame calculation + tournament consistency. Considered analog to Garry Kasparov in chess. OTHER LEGENDS: (1) KUNIHIKO TANIDA (Japan) — 3× World Champion; pioneering pre-computer era. (2) BEN SEELEY (USA) — 1993 World Champion; long-tenured US pro + author. (3) TAKUJI KASHIWABARA (France, Japanese-born) — 2× World Champion; renowned analyst + book author. (4) NAOKI WADA (Japan) — Multi-time Japan Meijin + finalist. MODERN TOP: (1) YUSUKE TAKANASHI (Japan) — 2022 World Champion. (2) KAZUKI OKAMOTO (Japan) — 2019 World Champion. (3) EMMANUEL CASPARD (France) — 2007 World Champion. JAPAN DOMINANT: 30+ of 45 World Championships won by Japanese players since 1977. Explains why Japan's Meijin title carries such prestige. Tamenori dominance in 1990s-2000s = universally acclaimed GOAT status.

Sources & provenance

Wikipedia — Reversi— Wikipedia
Wikipedia — Othello— Wikipedia
World Othello Federation— WOF
eOthello — Online play + rating— eOthello

Last verified 2026-08-25.verified