Betting calculatorOdds and probability

Sports Betting Odds Converter

Convert American odds to decimal odds, fractional odds, and implied probability.

Convert American odds

Result—

Enter the example values to calculate a result.

Convert American, decimal, and fractional odds
Odds formats describe the same payout in different ways. American odds use positive and negative prices, decimal odds show total return per unit staked, and fractional odds express profit relative to stake. This odds converter translates an American price into the other formats and its break-even probability.
For example, +150 American odds equal decimal 2.50 and fractional 3/2. A $10 winning bet at those odds returns $25 in total: $15 profit plus the original $10 stake.
Read the payout, not only the sign
Positive American odds show the profit from a $100 stake. Negative odds show the amount you need to risk to earn $100 profit. Decimal odds include the stake in total return, while fractional odds do not.
Use the probability output as a break-even figure. It includes any market margin embedded in that single price and may not represent the event’s true likelihood.
When odds conversion is useful
A consistent format makes it easier to compare sportsbooks, calculate parlay payouts, and evaluate expected value. Convert each leg before multiplying parlay prices, and use the current odds rather than a stored line when planning a wager.

How do I convert American odds to decimal odds?

For positive odds, divide the price by 100 and add 1. For negative odds, divide 100 by the absolute price and add 1.

What does +150 mean in betting?

A $100 stake at +150 wins $150 profit, plus the $100 stake returned, for $250 total return. The break-even probability is 40%.

What is the difference between decimal odds and fractional odds?

Decimal odds include the stake in the displayed total return. Fractional odds show profit relative to stake.