Implied Probability Calculator

Choose an odds format, enter the value, and instantly view the implied probability along with conversions to other formats.

Implied Probability

40.00%

Chance needed to break even

Decimal Odds

2.500

European format

American Odds

150

Moneyline format

Fractional Odds

3:2

UK format

Potential Profit

$150.00

Winnings excluding stake

Potential Return

$250.00

Stake + profit

Expected Value (break-even)

$0.00

Assuming true odds equal implied odds

How to Use This Calculator

  1. Select the odds format you have (decimal, American, or fractional).
  2. Enter the odds value. Add a stake if you want profit and return figures.
  3. Read the implied probability and converted odds in other formats.
  4. Use the results to compare bets, price contracts, or evaluate fair odds.

Formula

P = 1 / Decimal

Decimal = American ≥ 0 ? (American / 100 + 1) : (100 / |American| + 1)

Decimal = Fractional + 1

Implied probability reflects the break-even win rate. For a profitable wager, your estimated chance of success must exceed the implied probability.

Full Description

Sportsbooks quote odds in different styles depending on region. Converting between them reveals the implied win probability, which is essential for bankroll management, line shopping, and risk analysis. This calculator centralizes those conversions and adds profit projections based on stake size.

Remember that bookmakers build a margin (“vig”) into their odds, so implied probabilities across all outcomes typically sum to more than 100%. Adjust your models accordingly when searching for value bets.

Frequently Asked Questions

Why is implied probability important?

It shows the win rate required to break even. If you believe the true probability is higher, the wager has positive expected value.

What if the sportsbook includes vig?

Sum the implied probabilities of all mutually exclusive outcomes. Anything above 100% represents the bookmaker's edge. Divide each probability by the total to “remove” the vig.

Can decimal odds be less than 1?

No. Decimal odds represent total return per $1 staked, so they must be greater than 1. Values at or below 1 would imply guaranteed loss.

How do I convert my own probability to odds?

Use Decimal = 1 / P. Then convert to American or fractional using the formulas provided. You can price bets directly from your models this way.