Sportsbook Odds Calculator

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Sportsbook Odds Calculator

Use this calculator to convert between different odds formats (American, Decimal, Fractional), determine the implied probability of an outcome, and calculate your potential payout based on your stake.

American Odds Decimal Odds Fractional Odds
function toggleOddsInputs() { var type = document.getElementById("oddsInputType").value; document.getElementById("americanOddsSection").style.display = "none"; document.getElementById("decimalOddsSection").style.display = "none"; document.getElementById("fractionalOddsSection").style.display = "none"; if (type === "american") { document.getElementById("americanOddsSection").style.display = "block"; } else if (type === "decimal") { document.getElementById("decimalOddsSection").style.display = "block"; } else if (type === "fractional") { document.getElementById("fractionalOddsSection").style.display = "block"; } } function calculateOdds() { var stakeAmount = parseFloat(document.getElementById("stakeAmount").value); var oddsInputType = document.getElementById("oddsInputType").value; if (isNaN(stakeAmount) || stakeAmount 0) { decimalOdds = (americanOdds / 100) + 1; impliedProbability = 100 / (americanOdds + 100); } else { // americanOdds < 0 decimalOdds = (100 / Math.abs(americanOdds)) + 1; impliedProbability = Math.abs(americanOdds) / (Math.abs(americanOdds) + 100); } } else if (oddsInputType === "decimal") { var decimalInput = parseFloat(document.getElementById("decimalOddsInput").value); if (isNaN(decimalInput) || decimalInput 1.0 for a bet to have profit document.getElementById("result").innerHTML = "Please enter valid Decimal Odds (e.g., 2.50, 1.90). Must be greater than 1.0."; return; } decimalOdds = decimalInput; impliedProbability = 1 / decimalOdds; if (decimalOdds >= 2.00) { americanOdds = (decimalOdds – 1) * 100; } else { americanOdds = -100 / (decimalOdds – 1); } } else if (oddsInputType === "fractional") { var num = parseFloat(document.getElementById("fractionalOddsNumerator").value); var den = parseFloat(document.getElementById("fractionalOddsDenominator").value); if (isNaN(num) || isNaN(den) || num <= 0 || den 1 if ((num / den) = 2.00) { americanOdds = (decimalOdds – 1) * 100; } else { americanOdds = -100 / (decimalOdds – 1); } } // Calculate payout and profit based on decimal odds potentialPayout = stakeAmount * decimalOdds; potentialProfit = potentialPayout – stakeAmount; // Convert decimal odds to a simplified fractional representation for display var fractionalDisplay = ""; if (decimalOdds > 1) { var profitPart = decimalOdds – 1; var tolerance = 1.0E-9; // For floating point comparisons var bestN = 0; var bestD = 1; // Iterate through possible denominators to find a simple fraction for (var d = 1; d <= 100; d++) { // Limit denominator for practical display var n = profitPart * d; if (Math.abs(n – Math.round(n)) < tolerance) { bestN = Math.round(n); bestD = d; break; } } // Simplify the fraction (e.g., 2/4 to 1/2) function gcd(a, b) { return b === 0 ? a : gcd(b, a % b); } var commonDivisor = gcd(bestN, bestD); fractionalDisplay = (bestN / commonDivisor) + "/" + (bestD / commonDivisor); } else { fractionalDisplay = "N/A"; // Should not happen with valid odds } var resultHTML = "

Calculation Results:

"; resultHTML += "Stake Amount: $" + stakeAmount.toFixed(2) + ""; resultHTML += "American Odds: " + (americanOdds > 0 ? "+" : "") + americanOdds.toFixed(0) + ""; resultHTML += "Decimal Odds: " + decimalOdds.toFixed(2) + ""; resultHTML += "Fractional Odds: " + fractionalDisplay + ""; resultHTML += "Implied Probability: " + (impliedProbability * 100).toFixed(2) + "%"; resultHTML += "Potential Payout: $" + potentialPayout.toFixed(2) + ""; resultHTML += "Potential Profit: $" + potentialProfit.toFixed(2) + ""; document.getElementById("result").innerHTML = resultHTML; } // Initial call to set up the correct input visibility toggleOddsInputs(); // Initial calculation with default values calculateOdds(); .calculator-container { font-family: 'Arial', sans-serif; background-color: #f9f9f9; padding: 20px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1); max-width: 600px; margin: 20px auto; } .calculator-container h2 { color: #333; text-align: center; margin-bottom: 20px; } .calculator-container p { color: #555; margin-bottom: 15px; line-height: 1.6; } .calc-input-group { margin-bottom: 15px; } .calc-input-group label { display: block; margin-bottom: 5px; color: #333; font-weight: bold; } .calc-input-group input[type="number"], .calc-input-group select { width: calc(100% – 22px); padding: 10px; border: 1px solid #ddd; border-radius: 4px; font-size: 16px; box-sizing: border-box; } .calc-input-group input[type="number"]:focus, .calc-input-group select:focus { border-color: #007bff; outline: none; box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25); } .calculator-container button { background-color: #007bff; color: white; padding: 12px 20px; border: none; border-radius: 4px; cursor: pointer; font-size: 18px; width: 100%; transition: background-color 0.2s ease-in-out; } .calculator-container button:hover { background-color: #0056b3; } .calc-result { background-color: #e9f7ef; border: 1px solid #d4edda; border-radius: 4px; padding: 15px; margin-top: 20px; color: #155724; } .calc-result h3 { color: #155724; margin-top: 0; border-bottom: 1px solid #d4edda; padding-bottom: 10px; margin-bottom: 10px; } .calc-result p { margin-bottom: 8px; } .calc-result p strong { color: #0c3a1e; } .error { color: #dc3545; font-weight: bold; }

Understanding Sportsbook Odds

Sportsbook odds are a fundamental part of sports betting, representing both the probability of an event occurring and the potential payout for a successful wager. They are presented in various formats, each with its own way of expressing these two key pieces of information.

Types of Odds Formats

There are three primary formats for displaying odds:

  • American Odds (Moneyline Odds): Predominantly used in the United States, these odds are displayed with a plus (+) or minus (-) sign.
    • Positive Odds (+): Indicate how much profit you would make on a $100 stake. For example, +150 means a $100 bet would yield $150 profit (total payout $250).
    • Negative Odds (-): Indicate how much you need to stake to win $100 profit. For example, -200 means you need to bet $200 to win $100 profit (total payout $300).
  • Decimal Odds (European Odds): Popular in Europe, Canada, and Australia, these odds are straightforward. They represent the total payout (including your original stake) for every $1 staked. For example, 2.50 means a $100 bet would yield a total payout of $250 ($150 profit).
  • Fractional Odds (Traditional Odds): Commonly used in the UK and Ireland, these odds show the profit relative to your stake. For example, 3/2 (read as "three to two") means for every $2 you stake, you will win $3 profit. A $100 bet at 3/2 would yield $150 profit (total payout $250).

Implied Probability

Beyond just showing potential payouts, odds also reflect the sportsbook's assessment of the likelihood of an event happening. This is known as "implied probability." For instance, odds of 2.00 (Decimal) or +100 (American) or 1/1 (Fractional) suggest a 50% chance of the event occurring. The higher the implied probability, the more likely the event is to happen according to the bookmaker, and consequently, the lower your potential payout.

Why Use an Odds Calculator?

An odds calculator is an invaluable tool for bettors for several reasons:

  • Quick Conversions: Easily switch between American, Decimal, and Fractional odds to understand them in your preferred format.
  • Compare Odds: When different sportsbooks offer varying odds, converting them to a single format helps you identify the best value.
  • Understand Value: By calculating the implied probability, you can compare it to your own assessment of an event's likelihood. If you believe an event has a higher chance of happening than the implied probability suggests, you've found a "value bet."
  • Calculate Payouts: Instantly see your potential winnings for any given stake, helping you manage your bankroll and betting strategy.

How to Use This Calculator

  1. Enter Your Stake: Input the amount of money you wish to bet.
  2. Select Odds Format: Choose whether you are entering American, Decimal, or Fractional odds.
  3. Input Odds: Enter the odds according to the format you selected. For fractional odds, enter the numerator and denominator separately.
  4. Click "Calculate Odds": The calculator will instantly display the odds in all three formats, the implied probability, and your potential payout and profit.

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