You are Prisoner A. Choose Cooperate or Defect each round. Lower sentence (years) is better.
Rounds played: 0
Live Play
Pick your move this round (or press C / D)
Opponent strategy
Auto-play rounds:
Payoff (years): If both cooperate → 2 & 2. If both defect → 5 & 5. If you cooperate and opponent defects → you 10, opponent 0. If you defect and opponent cooperates → you 0, opponent 10.
Round controls & tips
Keyboard: C = Cooperate, D = Defect
Play several rounds and watch how opponent strategies respond. Tit-for-Tat: starts cooperating then mirrors your previous move. Grim Trigger: cooperates until you defect once, then defects forever.
Simulation controls
Run many rounds to see long-term behaviour — the game keeps cumulative years (lower = better).