Betting Odds Calculator

Convert odds between Decimal, Fractional, and American formats instantly. Also calculates implied probability from any odds.

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

How to Use This Calculator

  1. Select your odds format using the toggle (Decimal, Fractional, or American)
  2. Enter the odds value in the input field
  3. See the equivalent odds 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

What are decimal odds?

Decimal odds represent the total return per $1 staked, including your stake. For example, odds of 2.50 mean you receive $2.50 for every $1 bet (profit of $1.50).

What are American odds?

American odds use + and - signs. Positive odds (+150) show profit on a $100 bet. Negative odds (-200) show how much you need to bet to profit $100.

What are fractional odds?

Fractional odds like 3/2 mean you win $3 for every $2 staked. The first number is profit, the second is your stake amount.

What is implied probability?

Implied probability converts odds into a percentage showing how likely the bookmaker thinks the outcome is. Lower odds mean higher implied probability.