Odds Converter

Type odds in any format — decimal, fractional, or American — and see all three, plus the implied probability the bookmaker is really quoting.

Decimal
Fractional
American
Implied probability

How the conversions work

Fractional → decimal

Divide the numerator by the denominator and add 1 (your returned stake): 11/4 → 11 ÷ 4 + 1 = 3.75. Decimal odds are total return per unit staked, which is why they're always at least 1.

American → decimal

Positive odds show profit on a 100 stake: +275 → 275 ÷ 100 + 1 = 3.75. Negative odds show the stake needed to win 100: -150 → 100 ÷ 150 + 1 = 1.67.

Implied probability

For decimal odds: 1 ÷ odds. So 3.75 implies 1 ÷ 3.75 = 26.7%. Sum the implied probabilities of every outcome in a market and you'll get more than 100% — the overround, which is the bookmaker's margin. Our odds formats guide covers this in depth.

Common conversions at a glance

FractionalDecimalAmericanImplied %
1/21.50-20066.7%
4/51.80-12555.6%
EVS (1/1)2.00+10050.0%
6/42.50+15040.0%
3/14.00+30025.0%
10/111.00+10009.1%

FAQ

How do I convert fractional odds to decimal?

Divide the first number by the second and add 1. 11/4 becomes 3.75.

What is implied probability?

The win chance a price suggests: 1 ÷ decimal odds. Odds of 2.50 imply 40%. If you believe the true chance is higher than the implied probability, the bet has positive expected value.

What does evens mean?

EVS or 1/1: you win exactly your stake. Decimal 2.00, American +100, implied probability 50%.

Stop converting, start tracking

Zort reads odds in any format straight off your bet slip — point your camera and the AI scanner logs the stake, odds, and returns automatically, then shows your real P&L across every bookmaker.

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