Sports betting and prediction market calculators
25 calculators for odds, stakes and market prices.
How they work
Each one runs in your browser, works without JavaScript, keeps its inputs in the URL so a result is a link, and starts from Bandwagon's live numbers where they apply. Educational tool. Bandwagon does not take or place wagers.
Sports betting math
16 calculatorsConvert odds, size a stake, price a parlay, find a hedge or an arbitrage, and measure what a price is worth.
Odds Converter
American, decimal, fractional and implied probability, in both directions.
Implied Probability Calculator
The win chance a price implies, with the sportsbook's margin taken out.
Parlay Calculator
Up to 12 legs in any odds format: payout, combined odds and the real chance all of them win.
Parlay Odds by Number of Legs
What two to twelve legs at the same price pay, and the win rate each leg needs.
Hedge Calculator
How much to bet on the other side of an open bet to lock in the same result either way.
Arbitrage Calculator
Two- and three-way arbitrage: the stake split that locks in the same return, and the margin.
Expected Value Calculator
The average result of a bet if your win probability is right, and the edge over the price.
Vig Calculator
The juice on a market, and the fair no-vig odds for each side.
Kelly Criterion Calculator
Full, half and quarter Kelly stakes from the odds, your win probability and your bankroll.
Bankroll and Unit Size Calculator
Set a unit as a share of your bankroll and see how many losses in a row it takes to hurt.
Moneyline to Spread Calculator
Convert a moneyline to the point spread it is worth, with Bandwagon's fitted constants per sport.
Spread to Moneyline Calculator
Convert a point spread to the fair moneyline and win chance, per sport.
Teaser Calculator
Teased-leg cover chance and teaser break-even for 6, 6.5 and 7 point NFL and college football teasers.
Round Robin Calculator
Every k-leg parlay from your picks: how many, the total staked and the typical return by number of winners.
Futures Hedge Calculator
Hedge a futures ticket: the hedge amount, the locked profit and what a partial hedge does.
Closing Line Value Calculator
Compare the price you took with the closing price: improvement, probability gained and EV at the close.
Prediction markets
6 calculatorsTurn a contract price into a probability, take the margin out of a pair, and work out payouts and break-evens after fees.
Contract Price to Probability Calculator
Prediction-market contract price in cents to a probability, and a probability to a price.
Prediction Market De-Vig Calculator
Take the yes and no prices of a market and read the fair probability and the overround.
Prediction Market Payout Calculator
Contracts, price and a configurable fee: cost, payout, net profit, return and break-even.
Prediction Market Break-Even Calculator
The probability you need to break even at a contract price once fees are paid.
Market vs Model Edge Calculator
Pick a game from today's slate, enter a market price and see the gap to Bandwagon's model probability.
Cross-Market Arbitrage Calculator
The same event priced on two markets: the cheapest pair, the locked profit and the contracts for a budget.
Odds and analysis
3 calculatorsBandwagon's own model and crowd: the logistic that turns ratings into probabilities, and where the crowd and the model disagree.
Win Probability to Spread Calculator
Turn a win probability into the point spread the model would set, per sport.
Rating Gap to Win Probability Calculator
The model's logistic: a rating gap to a win probability, per sport, with the constants shown.
Crowd vs Model Gap Calculator
Pick a game from today's slate: the crowd's pick share against the model's win probability.
Where the live numbers come from
The slate pickers use Bandwagon's own model (odds, with its public backtest), the crowd's picks and the prices from Kalshi and Polymarket. Bandwagon's model, not a sportsbook line. We do not take wagers.
25 free calculators: odds converter, parlay, Kelly criterion, hedge, arbitrage, vig, prediction-market payout and break-even, and Bandwagon's model. Educational tool. Bandwagon does not take or place wagers.