Free calculators to help you bet smarter. Convert odds, calculate parlays, find bookmaker margins, and measure expected value — all in your browser, no sign-up needed.
Convert between decimal, fractional, and American (moneyline) odds instantly. Also shows implied probability for any odds format.
Calculate expected value for any bet. Enter your estimated probability and the odds offered to see if a bet has positive or negative EV.
Calculate combined odds, potential payout, and implied probability for multi-leg parlays and accumulators. Supports up to 20 legs.
Calculate the bookmaker margin (overround) for any market. See how much edge the bookmaker is taking and find fair odds for each outcome.
Calculate the optimal bet size based on your edge and bankroll. Supports full, half, and quarter Kelly to control variance.
Compare bookmaker odds against fair odds to find value bets. See edge percentage, expected value, and Kelly-suggested stakes for each selection.
Enter xG for each team and get a full correct score grid, 1X2 odds, over/under lines, and BTTS probabilities using the Poisson distribution.
Understand every Asian handicap line from DNB to -2.5. See payout scenarios, calculate returns, and convert between AH and 1X2 markets.
Calculate lay stakes, liability, and profit for qualifying bets, SNR free bets, and stake-returned free bets on betting exchanges.
Two-step matched betting workflow — calculate qualifying bet losses and free bet extraction profits. Works with any exchange commission.
Calculate guaranteed profit from free bets by laying on an exchange. Compares SNR vs SR free bets and shows optimal retention rates.
Split your stake across multiple selections to guarantee the same profit regardless of which one wins. Essential for multi-outcome markets.
Calculate the optimal hedge bet to lock in profit or minimize losses. Supports equal profit, break-even, and custom stake modes.
Compare bookmaker cash out offers against the mathematically fair value. See if the bookmaker is offering you a fair deal or skimming profit.
Compare flat, percentage, and Kelly staking strategies. Simulate up to 1,000 bets and see bankroll growth, drawdowns, and ROI for each method.
Calculate position sizes for bet365 vs Polymarket arbitrage opportunities. Uses Kelly Criterion for optimal bankroll management.