Mastermind

Colour-deduction game — one player sets a hidden 4-peg code; the other guesses, with black/white peg feedback each turn.

🌤indoor

What is Mastermind?

Mastermind is a two-player code-breaking game invented by Israeli postmaster and telecommunications expert Mordecai Meirowitz in 1970. One player secretly arranges four coloured pegs from six colours; the other has ten guesses. After each guess the codemaker gives feedback — a black peg for each guess in the right colour and position, a white peg for each right colour but wrong position. Sold over 55 million copies via Invicta Plastics (later Hasbro). A classic of both toy-shops and computer-science education.

Quick facts

Category

Puzzle Games

Type

Individual

Players

2–2

Where played

indoor

Country of origin

🇮🇱 Israel

Estimated origin

1970, Mordecai Meirowitz (Israeli postmaster); Invicta Plastics UK commercialised worldwide

Olympic

No

Popularity

global

Sources & provenance

Last verified 2026-08-24.verified