Rock Paper Scissors Strategy Calculator

Enter how often your opponent throws rock, scissors, and paper to find your best move plus win, draw, and loss probabilities, with an optional simulation.

Input

Enter how often your opponent throws rock, scissors, and paper to find your win rate for each move and the move most likely to win.

Opponent rock

percent

Opponent scissors

percent

Opponent paper

percent

The three values are normalized to add up to 100 percent automatically.

Result

Your best move

Paper

Win rate 40.0 percent

Draw 25.0 percent, loss 35.0 percent

Outcome by your move

You throw Rock

Win 35.0 percent

Draw 40.0 / loss 25.0 / expected 0.10

You throw Scissors

Win 25.0 percent

Draw 35.0 / loss 40.0 / expected -0.15

You throw Paper

Win 40.0 percent

Draw 25.0 / loss 35.0 / expected 0.05

Opponent move tendency

Random simulation

The opponent move is drawn from your input probabilities and played against your best move Paper.

Trials

times

How it works

Enter how often your opponent throws each move. The three values are normalized so they add up to 100 percent before the calculation.
Your win rate for a move equals the chance the opponent throws the move it beats. For example, if you throw rock, your win rate is the chance the opponent throws scissors.
The draw rate is the chance the opponent throws the same move, and the loss rate is the chance the opponent throws the move that beats you.
Expected value scores a win as 1, a draw as 0, and a loss as minus 1, giving the average score per round.
The simulation draws the opponent move at random from your input probabilities when you press the button, then plays the best move and shows the outcome breakdown.
Because the simulation uses random draws, a small number of trials can differ from the theoretical values. More trials bring the results closer to theory.

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