Free Betting Calculators

Betting Odds Calculator

Convert odds between Decimal, Fractional, and American formats instantly. Also calculates implied probability from any odds.

Implied Probability Calculator

Calculate the true probability implied by bookmaker odds. Enter odds for multiple outcomes to see the total probability and bookmaker margin.

No-Vig Calculator

Remove the bookmaker's margin to find fair odds. See what the odds would be without the bookmaker's built-in profit margin.

Odds Calculator

Quick and simple odds conversion tool. Enter odds in any format and see the equivalent in all other formats, plus the implied probability percentage.

Point Spread Calculator

Convert point spreads to moneylines and implied probabilities. See what a spread means in terms of win probability and equivalent moneyline odds.

Accumulator Bet Calculator

Calculate potential returns for accumulators with multiple selections. See how combined odds multiply your potential winnings. Supports win, lose, and void outcomes.

Double Bet Calculator

Calculate returns for a double bet (2 selections). Both selections must win for the bet to pay out. Shows combined odds and potential profit.

Parlay Calculator

Calculate combined odds and payouts for multi-leg parlay bets. Popular in US sports betting. Supports win, lose, and push outcomes for each leg.

Single Bet Calculator

Enter your stake and odds to instantly see potential returns and profit. Supports Decimal, Fractional, and American odds formats.

Treble Calculator

Calculate returns for a treble bet (3 selections). All three must win. Higher risk but bigger potential rewards than doubles.

Alphabet Calculator

Calculate returns for Alphabet bets with 6 selections. An Alphabet consists of 26 bets: 2 patents, 1 yankee, and a six-fold accumulator.

Canadian Calculator

Calculate returns for Canadian (Super Yankee) bets. A Canadian is 26 bets across 5 selections: 10 doubles, 10 trebles, 5 four-folds, and 1 five-fold accumulator.

Double Stakes About (DSA) Calculator

Calculate returns for Double Stakes About bets. A DSA is a conditional any-to-come bet between 2 selections where double the stake goes on the second selection.

Flag Calculator

Calculate returns for Flag bets with 4 selections. A Flag consists of 23 bets: 6 doubles, 4 trebles, 1 four-fold accumulator, and 12 single-stakes-about (SSA) pairs.

Goliath Calculator

Calculate returns for Goliath bets. A Goliath is 247 bets across 8 selections: 28 doubles, 56 trebles, 70 four-folds, 56 five-folds, 28 six-folds, 8 seven-folds, and 1 eight-fold.

Goliath Flag Calculator

Calculate returns for Goliath Flag bets with 8 selections. A Goliath Flag consists of 303 bets: 247 system bets and 56 SSA any-to-come pairs.

Heinz Calculator

57 bets on 6 selections: 15 doubles + 20 trebles + 15 four-folds + 6 five-folds + 1 six-fold. No singles, so you need at least 2 winners for a return.

Heinz Flag Calculator

Calculate returns for Heinz Flag bets with 6 selections. A Heinz Flag consists of 87 bets: 15 doubles, 20 trebles, 15 four-folds, 6 five-folds, 1 six-fold accumulator, and 30 SSA pairs.

Lucky 15 Calculator

15 bets on 4 selections: 4 singles + 6 doubles + 4 trebles + 1 four-fold. One winner guarantees a return. Many bookies offer bonuses for all 4 winning.

Lucky 31 Calculator

31 bets on 5 selections covering all combinations from singles to five-fold. One winner guarantees a return. Popular for horse racing with consolation bonuses available.

Lucky 63 Calculator

63 bets on 6 selections: all possible combinations. Maximum coverage for 6 picks. One winner guarantees a return, with potential for huge payouts if all 6 win.

Patent Calculator

7 bets on 3 selections: 3 singles + 3 doubles + 1 treble. Just one winner guarantees a return. More coverage than a Trixie but higher total stake.

Round Robin Calculator

Creates all possible parlays from your selections. Choose 3-8 picks and see every 2-way and 3-way combination. Great for spreading risk across multiple smaller parlays.

Single Stakes About (SSA) Calculator

Calculate returns for Single Stakes About bets. An SSA is a conditional any-to-come bet between 2 selections consisting of 2 bets.

Super Flag Calculator

Calculate returns for Super Flag bets with 5 selections. A Super Flag consists of 46 bets: 10 doubles, 10 trebles, 5 four-folds, 1 five-fold accumulator, and 20 SSA pairs.

Super Heinz Calculator

120 bets on 7 selections covering all combinations except singles. The ultimate system bet for confident punters. Requires 2+ winners for any return.

Super Heinz Flag Calculator

Calculate returns for Super Heinz Flag bets with 7 selections. A Super Heinz Flag consists of 162 bets: 120 system bets and 42 SSA any-to-come pairs.

Trixie Calculator

4 bets on 3 selections: 3 doubles + 1 treble. You need at least 2 winners to get a return. Lower risk than a treble with decent returns.

Union Jack Patent Calculator

Calculate returns for Union Jack Patent bets. 9 selections in a 3×3 grid with a Patent (3 singles + 3 doubles + 1 treble) on each of the 8 lines, totaling 56 bets.

Union Jack Round Robin Calculator

Calculate returns for Union Jack Round Robin bets. 9 selections in a 3×3 grid with a Round Robin (3 doubles + 1 treble + 6 SSA) on each of the 8 lines, totaling 80 bets.

Union Jack Trebles Calculator

Calculate returns for Union Jack Trebles bets. 9 selections arranged in a 3×3 grid with 8 treble bets along rows, columns, and diagonals.

Union Jack Trixie Calculator

Calculate returns for Union Jack Trixie bets. 9 selections in a 3×3 grid with a Trixie (3 doubles + 1 treble) on each of the 8 lines, totaling 32 bets.

Yankee Calculator

11 bets on 4 selections: 6 doubles + 4 trebles + 1 four-fold. Need at least 2 winners for a return. Popular system bet with good balance of risk and reward.

Arbitrage Bet Calculator

Find guaranteed profits by betting on all outcomes across different bookmakers. Enter odds from multiple bookies to calculate stake distribution for risk-free returns.

Closing Line Value Calculator

Measure your betting edge by comparing your odds to the closing line. CLV is the best predictor of long-term betting profitability.

Dutching Calculator

Calculate optimal stakes for dutching multiple selections in the same market. Distribute your total stake to get equal returns regardless of which selection wins.

Expected Value Calculator

Determine if a bet has positive expected value (+EV). Enter odds and your estimated true probability to see if the bet is profitable long-term.

Half Point Calculator

Calculate the cost and value of buying half points on point spreads. Determine if paying extra juice to move off a key number is worth it.

Hold Calculator

Calculate the bookmaker's margin (vig/juice) on any two-way market. See implied probabilities, fair odds without the vig, and identify which bookmakers offer the best value.

Kelly Criterion Calculator

Calculate the mathematically optimal bet size based on your edge and bankroll. Maximize long-term growth while managing risk.

Strike Rate Calculator

Track your betting win percentage and compare it to the break-even rate for your average odds. Calculate ROI, edge, and average profit per bet to evaluate your performance.

Surebet Calculator

Calculate guaranteed profits from surebet opportunities. Enter odds from different bookmakers to find risk-free betting opportunities across 2-way and 3-way markets.

Win/Loss Calculator

Track your betting performance with win rate, ROI, and profit per bet. Enter your betting record to analyze your long-term results.

Each Way Calculator

Calculate returns for each-way bets. Enter your stake, odds, and place terms to see win returns, place returns, and potential profit for each-way wagers.

Hedge Bet Calculator

Lock in profit or minimize losses by betting against your original bet. Calculate the exact hedge stake for guaranteed profit.

Middle Calculator

Calculate potential profit from middle betting opportunities. Find situations where two opposing bets can both win, giving you a risk-free shot at a big payout.

Asian Handicap Calculator

Calculate Asian handicap bet outcomes. Enter the handicap, odds, and match score to determine your return for whole, half, and quarter Asian handicap bets.

Bonus Bet Conversion Calculator

Calculate how much guaranteed profit you can extract from free bets and bonus bets. Find the optimal lay stake and see your conversion rate.

Lay Bet Calculator

Calculate lay bet stakes, liability, and profit for betting exchange wagers. Find the optimal lay stake to match your back bet and see potential outcomes.

Matched Betting Calculator

Calculate optimal lay stakes for matched betting. Supports normal qualifying bets and free bets (stake returned and stake not returned) with exchange commission.

Poisson Calculator

Predict match outcomes using the Poisson distribution. Enter expected goals for each team to see probabilities for every scoreline, match result, over/under, and BTTS markets.

Action

Any wager placed on a sporting event; also used to indicate a bet is live and valid.

Against the Spread (ATS)

A team's record when measured against the point spread rather than the outright result.

Arbitrage Betting

Placing bets on all possible outcomes across different bookmakers to guarantee a profit regardless of the result.

Asian Handicap

A form of spread betting popular in soccer that eliminates the draw outcome by applying fractional or whole-number handicaps to one or both teams.

Bad Beat

A bet that appears certain to win but loses due to a last-minute or highly improbable event.

Bankroll

The total amount of money a bettor has set aside exclusively for wagering, separate from personal finances.

Betting Handle

The total amount of money wagered on a particular event or during a given time period.

Betting Limits

The minimum and maximum amounts a bookmaker will accept on a single bet.

Bonus Bet (Free Bet)

A promotional bet where the bookmaker provides a stake; if it wins, the bettor receives the profit but typically not the original stake.

Buying Points

Paying for a more favorable point spread or total by accepting worse odds, often used to cross key numbers like 3 and 7 in football.

Cash Out

A feature that lets bettors settle a bet before the event concludes, locking in a profit or limiting a loss.

Chalk

Slang for the favorite in a game or event; 'betting the chalk' means backing the expected winner.

Closing Line Value (CLV)

The difference between the odds at which you placed your bet and the final closing odds, used as a measure of betting skill.

Cover

When a team wins by enough points to beat the point spread, the team is said to have covered.

Double Chance

A bet that covers two of three possible outcomes in a soccer match (home/draw, away/draw, or home/away), reducing risk at the cost of lower odds.

Edge

A bettor's perceived advantage over the sportsbook, where the true probability of an outcome exceeds the implied probability of the odds.

Even Money

A bet where the potential profit equals the stake — decimal odds of 2.00, fractional 1/1, American +100.

Expected Value (EV)

The average amount a bettor can expect to win or lose per bet over the long run.

Fade the Public (Contrarian Betting)

A strategy of betting against the side that the majority of recreational bettors favor, based on the theory that public sentiment creates value on the opposite side.

Favorite vs Underdog

The favorite is expected to win (lower odds/shorter price), while the underdog is expected to lose (higher odds/longer price).

Futures Bet

A bet placed on an event that will be decided in the future, such as a season championship or tournament winner.

Hedging

Placing a bet on the opposite side of an existing wager to guarantee a profit or reduce potential loss regardless of the outcome.

Hook

A half-point in a point spread (e.g., -3.5 instead of -3) that eliminates the possibility of a push.

Implied Probability

The probability of an outcome as suggested by the betting odds, including the bookmaker's margin.

Juice / Vigorish (Vig)

The commission charged by the bookmaker on each bet, built into the odds.

Kelly Criterion

A mathematical formula that determines the optimal bet size based on perceived edge and bankroll.

Key Numbers

The most common margins of victory in a sport, making certain point spreads more significant than others.

Line Movement

A change in the odds or point spread after the opening line is released, driven by betting action, injuries, weather, or new information.

Line Shopping

Comparing odds across multiple bookmakers to find the best available price for a given bet.

Live Betting (In-Play)

Placing bets on an event while it is in progress, with odds updating in real time.

Matched Betting

A technique that uses sportsbook promotions (bonus bets, odds boosts) combined with opposing bets to extract guaranteed profit with minimal risk.

Middling

Betting both sides of a game at different point spreads, aiming to win both bets if the final margin lands between the two spreads.

Moneyline

A bet on which team or player will win outright, with no point spread involved.

No Action

A bet that is cancelled and the stake returned to the bettor, typically due to a postponed event, scratched player, or voided conditions.

Odds Boost

A promotion where the bookmaker temporarily increases the odds on a specific market, giving bettors enhanced potential returns.

Odds Formats

The three main ways odds are displayed — Decimal, Fractional, and American (Moneyline).

Oddsmaker / Bookmaker

The person or organization that sets betting lines and odds, manages risk, and accepts wagers on sporting events.

Off the Board

A game or market that the sportsbook has temporarily removed from betting, usually due to uncertainty such as injuries or weather.

Opening Line / Closing Line

The opening line is the first set of odds released; the closing line is the final odds before the event starts.

Over/Under (Totals)

A bet on whether the combined score of a game will be over or under a set number.

Parlay (Accumulator)

A single bet that links two or more selections; all must win for the bet to pay out.

Pick'em

A game where neither team is favored -- the point spread is zero, meaning bettors simply pick the winner.

Player Prop vs Game Prop

Player props are bets on individual performance (e.g., total passing yards), while game props are bets on team or match events (e.g., first team to score).

Point Spread

A handicap applied to level the playing field between the favorite and the underdog.

Profit Boost

A promotion that increases the profit portion of a winning bet by a percentage (e.g., +50% profit), distinct from an odds boost which increases the odds themselves.

Prop Bet (Proposition Bet)

A bet on a specific occurrence within a game that may not directly affect the final outcome.

Public Betting Percentage

The proportion of total bets placed on each side of a market, reflecting where the majority of recreational bettors have wagered.

Push

A bet that results in a tie against the spread or total, with the stake returned to the bettor.

Qualifying Bet

A bet that must be placed to activate or unlock a promotional offer, often subject to minimum odds and stake requirements.

Reload Bonus

A promotional deposit bonus offered to existing customers on subsequent deposits, as opposed to a first-time sign-up bonus.

Reverse Line Movement

When the betting line moves in the opposite direction of where the majority of public bets are placed, indicating sharp (professional) money on the other side.

Risk-Free Bet

A promotion where the bookmaker refunds the stake (usually as a bonus bet) if the initial bet loses.

ROI (Return on Investment)

The percentage of profit or loss relative to the total amount wagered.

Round Robin

A combination bet that creates multiple parlays from a group of selections, covering different subset combinations.

Run Line / Puck Line

A sport-specific point spread -- the run line is a fixed 1.5-run spread in baseball (MLB) and the puck line is a fixed 1.5-goal spread in hockey (NHL).

Same-Game Parlay

A parlay where all selections come from the same game or event.

Sharp vs Square

Sharp bettors are professionals who bet with an edge; square bettors are recreational bettors who typically follow public sentiment.

Site Credit

Non-withdrawable funds added to a betting account that can be used to place bets, with winnings typically being withdrawable.

Stale Line

Odds that have not been updated to reflect new information (such as injuries or lineup changes), creating a potential value opportunity for alert bettors.

Steam Move

A sudden, sharp line movement caused by heavy betting action from professional bettors or syndicates.

Straight Bet

A single wager on one outcome -- a moneyline, point spread, or total -- as opposed to a parlay or combination bet.

Teaser

A type of parlay where the bettor can adjust the point spread or total in their favor, in exchange for reduced odds.

Tout

A person or service that sells betting picks or predictions, often with exaggerated claims of success rates.

Units

A standardized measure of bet size relative to a bettor's bankroll, used to track results and compare performance regardless of actual dollar amounts.

Variance (in Betting)

The natural fluctuation in results that occurs even when making positive expected value bets.

Wagering Requirements (Rollover)

The number of times a bonus or deposit must be wagered before winnings can be withdrawn.