Free sports betting calculators
The calculators promo and arbitrage bettors use every day, free and with no account. Type in the odds you see at your sportsbooks and each one sizes the bets or tells you what the price is worth.
Hedging and promo conversion
Bet both sides of a market to lock in a result, clear a rollover or turn a bonus into cash.
- Arbitrage CalculatorCheck whether two or three prices are an arb and split your stake so every outcome pays the same.
- Free Bet CalculatorTurn a bonus bet into cash with the exact hedge stake, guaranteed profit and conversion rate.
- Risk-Free Bet CalculatorHedge a second chance or no-sweat bet so you profit whether it wins or is refunded as a bonus bet.
- Low Hold CalculatorSee the hold on any market and size both sides for cheap betting volume, including split legs.
Pricing and bet sizing
Work out what a price is really worth and how much of your bankroll it deserves.
- No-Vig CalculatorStrip the vig from a two-way market to get fair odds and win probability, four devig methods.
- Expected Value CalculatorCompare the odds you can bet with fair no-vig odds to see what a bet is worth on average.
- Kelly Criterion CalculatorSize a bet from your edge and bankroll, with full, half and quarter Kelly.
- Odds ConverterConvert between American, decimal and fractional odds and implied probability.
- Prediction Market Odds ConverterTurn a Kalshi or Polymarket contract price into American and decimal odds and a payout.
Free now, free for good
These calculators stay free. They work on odds you type in; BreadSync Pro finds the odds for you, with a live screen of 130+ sportsbooks that surfaces arbs, low holds, +EV bets and the best free bet conversions as the lines move.
See BreadSync Pro21+. Calculator results are estimates for information only, not betting advice or a guarantee of profit. BreadSync is not a sportsbook and does not accept wagers. If gambling stops being fun, call 1-800-GAMBLER.