Race friends in real-time multiplayer (free signup required)
Compete for daily prizes and streaks
Climb global rankings and earn achievements
Mastermind is a classic code-breaking logic puzzle invented in 1970. The online version lets you play instantly in your browser — no board, no pegs, no setup. Just pure deduction.
A secret color code is hidden — your job is to crack it using logic and the feedback from each guess. Every attempt tells you which colors are right and whether they're in the correct position. It typically takes 4–6 guesses for beginners, and expert players can solve it in 3. No download, no account needed to try it above.
What sets Mastermind Arena apart is the competitive layer. Race another player on the same code in real time, take on friends in Classic turn-based mode, or compete in the daily challenge where everyone gets the same puzzle. Free signup unlocks all multiplayer features and score tracking.
A fresh puzzle is released every day for all players. Solve the same code as everyone else, compare your attempts, and build a daily streak. Top solvers earn bonus points and appear in the daily champions hall of fame.