Odds Converter

Four odds formats explained

American odds show how much you win on a $100 stake (positive odds like +150) or how much you must bet to win $100 (negative odds like -150). Positive means underdog, negative means favorite.

Decimal odds show total return per unit staked, including your original stake. Decimal 2.50 means $1 returns $2.50 total. Common in Europe, Australia, and most betting exchanges.

Fractional odds show profit relative to stake. 5/2 means $2 wagered wins $5 profit. Traditional in UK horse racing and some European markets.

Implied probability shows the market-implied win chance. Convert any odds format to probability to compare value across different books and markets.

When to use each format

American odds are standard at US sportsbooks like DraftKings, FanDuel, BetMGM, and Caesars. If you bet in the US, you see American odds everywhere.

Decimal odds are common in Europe, Asia, and on betting exchanges like Betfair. Many sharp bettors prefer decimal because the math is simpler.

Fractional odds are traditional in UK betting shops and horse racing. Some US sportsbooks offer a fractional display option.

Implied probability is useful when comparing value. Convert the market odds to probability, then compare to your own estimate to find edge.

Quick conversion examples

American -110 = Decimal 1.91 = Fractional 10/11 = 52.4% implied probability. This is standard juice on NFL and NBA point spreads.

American +200 = Decimal 3.00 = Fractional 2/1 = 33.3% implied probability. A +200 underdog wins your stake back plus twice the stake in profit.

American -200 = Decimal 1.50 = Fractional 1/2 = 66.7% implied probability. A heavy favorite where you risk $200 to win $100.

FAQ

What is the difference between American and Decimal odds?

American odds show profit relative to $100 (positive) or stake required to win $100 (negative). Decimal odds show total return including your original stake. Decimal 2.00 equals American +100 equals even money where you double your money on a win.

How do I convert +150 American to decimal?

Divide by 100 and add 1. So +150 divided by 100 equals 1.50, plus 1 equals 2.50 decimal. A $1 stake at decimal 2.50 returns $2.50 total, which is $1.50 profit plus your $1 stake back.

How do I convert -150 American to decimal?

Divide 100 by the absolute value and add 1. So 100 divided by 150 equals 0.667, plus 1 equals 1.667 decimal. A $1.50 stake returns $2.50 total, which is $1 profit.

What does implied probability mean?

Implied probability is the win chance suggested by the odds. It includes the bookmaker margin (vig), so all outcomes in a market sum to more than 100 percent. To find true fair probability, use a no-vig calculator to remove the margin.

Why do some bettors prefer decimal odds?

Decimal odds make payout calculation trivial: multiply stake by decimal odds to get total return. They also make it easy to compare across markets since higher decimal always means better price, regardless of whether the bet is a favorite or underdog.