Free calculator

Odds converter

Convert odds between decimal (2.50), fractional (3/2) and American (+150) formats, and see the implied probability.

Decimal—
Fractional—
American—
Implied probability—

Fractions are simplified to the nearest fraction with a bottom number of 100 or less, so some results are approximate.

We never store what you type, and nothing is sent to bookmakers. With JavaScript switched on, the calculation happens entirely on your phone.

The three formats

Bookmakers in Zimbabwe use decimal odds, but you may see other formats on international websites, apps or TV.

DecimalFractionalAmericanImplied probability
1.501/2−20066.67%
2.001/1 (evens)+10050.00%
2.503/2+15040.00%
3.002/1+20033.33%
5.004/1+40020.00%

How the conversions work

  • Fractional to decimal: divide the top number by the bottom, then add 1. 3/2 → 1.5 + 1 = 2.50.
  • Decimal to fractional: subtract 1 and write it as a fraction. 2.50 → 1.50 → 3/2.
  • American to decimal: for +150, divide by 100 and add 1 (2.50). For −200, divide 100 by 200 and add 1 (1.50).
  • Decimal to American: if the odds are 2.00 or more, (decimal − 1) × 100 with a plus sign. If below 2.00, −100 ÷ (decimal − 1).

Some decimals do not convert to a neat fraction. The converter shows the closest simple fraction (with a bottom number of 100 or less).

Which format should I use?

Stick to decimal. It shows the total return per $1 directly, which makes payouts easy: stake × odds. See how to read betting odds.