Sports Mathematics Utility
Football Odds & Probability Calculator
Accurately convert between Decimal, Fractional, and American odds formats. Calculate implied win probabilities and measure the true bookmaker margin (overround).
Odds Conversion & Payout
Implied Win Probability
40.0%
Decimal
2.50
Fractional
3/2
American
+150
Total Payout
$250.00
1X2 Bookmaker Overround (Margin)
Enter the 3-way match prices to reveal the bookmaker house edge and calculate true normalized probabilities.
Bookmaker Edge / Margin
3.67%
Home Fair %
49.4%
Draw Fair %
27.5%
Away Fair %
23.1%
Mathematical Methodology & Disclaimers
Implied probability is calculated using the formula: Implied Probability (%) = (1 / Decimal Odds) * 100. When bookmakers price a match, the sum of probabilities across all outcomes exceeds 100%. This surplus is known as the overround or bookmaker margin. This tool executes pure mathematical conversions and does not provide gambling advice, financial tips, or guarantees of winning outcomes.