Convert odds between every format.
Type a price in any format — American, decimal, fractional, or implied probability — and read the other three instantly. Exact math, no nearest-fraction rounding.
How odds formats relate
American odds carry the sign. A negative price is the amount you risk to win 100: -110 risks 110 for 100 profit. A positive price is the profit on a 100 stake: +150 pays 150. The sign is the market’s shorthand for favorite and underdog, and it flips at even money — which is why the scale jumps from -100 to +100 with nothing in between.
Decimal odds are total return. Multiply your stake by the decimal number and you get back stake plus profit: 1.91 turns 100 into 191. Decimal is the cleanest format for math — parlays multiply, expected value drops straight out — which is why every serious pricing model works in decimals and converts at the edges.
Fractional odds are profit over stake. A 3/2 quote pays 3 units of profit for every 2 staked. This converter shows the exact reduced fraction of the number you typed rather than snapping to the nearest traditional quote — 1.91 is exactly 91/100, and pretending it is 10/11 hides a real difference in price.
Implied probability is the break-even rate. Every price is a probability statement: -110 says the book breaks you even at 52.4%. That number still includes the book’s margin. To see the fair probability a two-sided market implies, strip the juice with the vig calculator.
How the converter works
01
Type a price into any of the four fields — American, decimal, fractional, or implied probability.
02
The other three recompute from the exact value you entered, not a rounded lookup table.
03
Compare the implied probability against your own number before you take the price.
Odds conversion questions
- How do you convert American odds to decimal?
- Positive American odds: divide by 100 and add 1, so +150 is 2.50. Negative: divide 100 by the absolute value and add 1, so -110 is 1.91. The decimal number is your total return per unit staked, stake included.
- What implied probability does a price carry?
- For negative odds, |odds| / (|odds| + 100): -150 implies 60%. For positive odds, 100 / (odds + 100): +150 implies 40%. That figure still contains the book’s margin — strip it with the vig calculator to get a fair number.
- Why does the fractional field show 91/100 instead of 10/11?
- The converter reports the exact reduced fraction of the number you typed. Traditional bookie fractions are approximations — 10/11 is 1.909, not 1.91 — and the difference between the exact fraction and the familiar quote is precisely what the rounding costs you.
- Is the odds converter free?
- Yes. Free, no account, and the math runs in your browser. Tracking your picks and grading them against the closing line is part of RunLC Pro.
Converting a price you are about to bet? Track the pick and we will grade it against the closing line.