Separate an attractive payout from an informed decision. Compare offered odds with your own probability estimate and see how the expected result changes.
Explore the math free. Sports app access is separate.
The price is one input. Your probability is the other.
Your estimate clears the break even threshold before costs.
Your probability is unverified. Assumes a binary win or loss at the entered odds. Excludes fees, spreads, and execution costs. Expected value is an average, not a guaranteed outcome.
From question to decision
The price tells you the win probability needed to break even before costs. A +100 price requires a 50% win rate; it does not establish the real chance of winning.
Start with implied probability, then account for fees and the evidence behind your own estimate.
At +100, a 55% estimate produces $10 of modeled expected profit per $100 staked. Change the estimate to 45% and the modeled value becomes negative.
Expected value is a weighted average over possible outcomes, not a prediction of the next result.
Move the probability in both directions. A small apparent edge that disappears under a modest change deserves closer research and conservative sizing.
Use the no vig and Kelly calculators to understand market margin and sizing assumptions. Neither validates the probability you enter.
Before you get started
A clearer view of the market
Sports subscriptions and market availability apply. No outcome is guaranteed.