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Odds Converter

Odds are expressed differently around the world — American, decimal, and fractional formats all describe the same thing. This tool converts between all formats instantly and shows you the implied probability behind any line.

GamblersGuide Tool

Odds converter

Enter odds in any format

Enter American odds: e.g. -110, +150, -350

Quick examples

Implied probability

52.38%

Chance of winning implied by these odds

Profit on $100

$90.91

if this outcome wins

American odds · input

-110

Bet $110 to win $100

Decimal odds

1.909

$100 bet returns $190.90 total

Fractional odds

10/11

Win 10 units per 11 wagered

Implied probability

52.38%

1 in 1.9 chance

Win: 52.38%Lose: 47.62%

Odds formats explained

American odds show how much you win on a $100 bet (if positive) or how much you must bet to win $100 (if negative). Decimal odds multiply your stake by the decimal to get total return including stake. Fractional odds show profit relative to stake — 5/1 means win $5 for every $1 bet. Implied probability is the percentage chance the odds imply for that outcome winning.

How to read odds

American odds — The format used by US sportsbooks. Negative numbers (e.g. -110) show how much you need to bet to win $100. Positive numbers (e.g. +150) show how much you win on a $100 bet.

Decimal odds — Common in Europe and Australia. Multiply your stake by the decimal to get your total return including your original bet. Odds of 2.00 is even money.

Fractional odds — Traditional UK format. 5/1 ("five to one") means you win $5 for every $1 wagered. 1/2 ("one to two") means you win $1 for every $2 wagered — a heavy favorite.

Implied probability — The most important number. This strips away the format and shows the raw percentage chance the odds are implying. Always compare implied probability to your own estimate of the true probability to assess whether a bet has value.