Betting Odds Converter
Convert decimal odds to American and fractional formats, and calculate the implied probability and expected profit per $100 staked.
Results
What is it?
This calculator converts decimal odds (European format) into American (moneyline) odds and reveals the implied probability and expected profit. Decimal odds represent your total return per unit staked, while American odds show profit on a $100 bet (+) or the stake needed to win $100 (รขหโ). Implied probability is the bookmaker's estimated chance of the outcome occurring รขโฌโ and summing all outcome probabilities gives you the vig/overround, the bookmaker's margin.
How to use
Enter the decimal odds for the outcome you are analyzing. The calculator instantly shows the equivalent American moneyline odds, the implied probability baked into those odds, and the expected profit if you stake $100.
Example scenario
A bookmaker offers 2.50 decimal odds on a football team to win. The implied probability is 1/2.50 = 40%. The American equivalent is +150 (profit of $150 per $100 staked). If you believe the team's true probability of winning is 45%, there is positive expected value in this bet.
Pro tip
Bookmakers build an "overround" (vig) by shading odds below true probability. Summing the implied probabilities of all outcomes will total >100% รขโฌโ the excess percentage is their margin. Always compare implied probability against your own assessed probability to identify value bets. For educational and mathematical purposes only.