Convert Betting Odds

Switch decimal, fractional and American formats and read the implied probability.

Please enter valid odds
Results
Decimal --
Fractional --
American --
Implied Probability --

How to Use This Calculator

  1. Tap the toggle to set your odds format (Decimal, Fractional, or American)
  2. Drop the odds value into the input field
  3. Instantly see the same odds rendered in all three formats, plus implied probability

Examples:

  • Decimal: 2.50
  • Fractional: 3/2
  • American: +150 or -200

Formula

Decimal to Fractional: Fractional = Decimal - 1 (expressed as a fraction)

Decimal to American:

  • If Decimal >= 2.00: American = (Decimal - 1) x 100
  • If Decimal < 2.00: American = -100 / (Decimal - 1)

Implied Probability: 1 / Decimal Odds x 100%

Frequently Asked Questions

How do decimal odds work?

Decimal odds show the full return per $1 staked, stake included. So odds of 2.50 hand you back $2.50 for every $1 wagered, which is $1.50 in profit.

How do American odds work?

American odds run on + and - signs. A positive number like +150 shows the profit on a $100 bet. A negative number like -200 shows how much you need to stake to clear $100 in profit.

How do fractional odds work?

Fractional odds such as 3/2 mean $3 in winnings for every $2 you put down. The first figure is your profit, the second is the stake it’s based on.

What does implied probability mean?

Implied probability turns odds into a percentage that reflects how likely the bookmaker rates the outcome. The shorter the odds, the higher that implied probability climbs.