💰 Expected Value Calculator

Master Expected Value: The Foundation of Profitable Sports Betting

Expected Value (EV) is the single most important concept in professional sports betting mathematics. It represents the average amount you can expect to win or lose per bet over the long run, calculated by multiplying your win probability by potential profit and subtracting your loss probability multiplied by stake amount. Positive EV (+EV) bets are the holy grail of sports betting—these are wagers where the odds offered by the bookmaker are better than the true probability of the outcome, creating a mathematical edge for the bettor across NFL, NBA, NHL, MLB, NCAAF, and soccer markets.

Our EV calculator instantly determines whether a bet has positive or negative expected value by comparing bookmaker odds against your assessed true probability. For example, if you believe an NBA team has a 55% chance to cover the spread, but the odds imply only 50% probability (even money), you've found a +EV opportunity worth 5% edge. Over hundreds of bets, this edge compounds into significant profits. The calculator also computes ROI (Return on Investment) percentage, showing exactly how much profit you can expect per dollar wagered when repeating similar edges repeatedly.

Professional bettors never place wagers without first calculating EV. This discipline separates gamblers from investors—winning bettors understand that short-term variance is irrelevant if the underlying mathematics are sound. By consistently identifying and betting only +EV opportunities, you guarantee long-term profitability regardless of individual game outcomes. Use this tool to validate every bet against your probability models, historical data, and expert analysis from BetLegend to ensure every dollar wagered carries a positive mathematical expectation for sustained bankroll growth.