Free Sports Betting Calculators
12 calculators built for systematic bettors. From expected value and no-vig fair odds to Kelly staking and arbitrage stakes — the math you need, free.
Expected Value Calculator
Calculate the EV of any bet given odds and your estimated true probability. Positive EV = the bet has long-term edge.
Use when: evaluating whether a specific bet has mathematical edge Sharp FoundationNo-Vig Calculator
Strip the bookmaker's margin from any market to see the true implied probabilities and fair odds. The first step in any value bet assessment.
Use when: benchmarking odds against fair value before placing Guaranteed ProfitArbitrage Calculator
Enter both-side odds and stake to calculate exact stakes for guaranteed profit regardless of outcome. Covers 2-way and 3-way markets.
Use when: you've found an arb — need to know exact stakes for each side Bankroll SizingKelly Criterion Calculator
Calculate optimal stake size based on your edge and bankroll. Full Kelly, Half Kelly, and Quarter Kelly outputs to match your risk tolerance.
Use when: sizing stakes on a +EV bet you're confident in Book MarginVig Calculator
Calculate the exact vig (juice) percentage a bookmaker is charging on any market. Helps compare book efficiency across different markets.
Use when: comparing book margin across soft books to find the best prices Market EfficiencyHold Calculator
Calculate the hold percentage of a market — how much the book keeps on average. Low-hold markets are where systematic edge is most reliable.
Use when: filtering markets to focus on thin-margin books and eventsImplied Probability Calculator
Convert any odds format (decimal, American, fractional) to implied probability. Quick sanity check before comparing against your own estimates.
Use when: converting odds to probabilities for EV comparisonOdds Converter
Convert between decimal, American (moneyline), and fractional odds instantly. Essential when working across different regional books.
Use when: comparing odds from US (+150) vs European (2.50) booksPoisson Distribution Calculator
Model goal and score probabilities for soccer and hockey using the Poisson distribution. Build your own probability estimates for any scoreline.
Use when: building your own match model to compare against bookmaker linesPoint Spread Calculator
Convert point spreads to moneyline equivalents and vice versa. Useful when comparing spread prices across books that quote differently.
Use when: comparing spread vs moneyline pricing across booksParlay Calculator
Calculate parlay payout for any number of legs. Useful for checking whether a book is offering fair parlay prices or compounding extra vig.
Use when: verifying parlay odds are correctly priced before bettingHalf Point Calculator
Calculate the value of buying or selling half points on spreads and totals. Know when a key number adjustment is worth the price move.
Use when: deciding whether to buy off key numbers (3, 7 in NFL)Bonus Bet Conversion Calculator
Calculate the real cash value of bonus bets and free bet credits. Find the optimal hedge to lock in a guaranteed cash payout from any bonus.
Use when: converting a sportsbook free bet into guaranteed cash profitBeyond Calculators: Real-Time Scanning
Calculators are for one bet at a time. FairOdds Terminal runs the same math across hundreds of markets continuously — surfacing +EV bets, arbitrage opportunities, and Pinnacle dropping odds alerts as they happen.