MARKET ONTOLOGYSTATISTICS & PROBABILITY

    MO STATS · FREE PUBLIC TOOLS

    Work out the odds.
    Understand the decision.

    Calculate probabilities, compare payoffs, and simulate uncertainty. Use every calculator free. Create an account to save your work and compete.

    No account to calculateNo real-money wageringTransparent assumptions

    CALCULATOR

    Expected value

    Calculate the average net payoff of a repeated two-outcome decision.

    Free
    Expected value inputs
    Use the same currency or unit for both outcomes.
    Enter a negative number; exclude any returned stake.

    Calculations run in your browser. Saving and publishing are optional.

    Start with your assumptions

    Enter values and calculate to see the result, method, and assumptions.

    PUT YOUR JUDGMENT TO WORK

    Compete on decisions.

    Free entry

    Card Odds

    Estimate the chance of a card event. Compete on the accuracy of your probability judgment.

    Free entry

    Bankroll Arena

    Choose a stake for a simulated opportunity. Compete on the quality of the decision under stated odds.

    Games award nonredeemable MO Chips and decision scores. Chips cannot be bought, transferred or exchanged, and game results never earn anything of monetary value. Subscribing gives no competitive advantage.