Odds Calculator

Your details

Choose how your odds are written. Ratio and fractional are common in probability and UK betting. Decimal is European standard. American (moneyline) is used by US sportsbooks.
In "1 to 4" odds, this is the 1: the number of ways the event succeeds.
In "1 to 4" odds, this is the 4: the number of ways the event fails.
Turn on to enter a stake amount and see your potential profit and total return.
Turn on to find the probability of this same outcome repeating a given number of times in a row (e.g. flipping heads 5 times).
Requires a second set of odds for the opposite outcome. The calculator will strip the house margin and show fair-odds probability for both sides.
Implied probabilityUnlikely
20%
Probability it does not happen80%
Equivalent decimal odds5
Odds against (per 1 for)4
Equivalent American odds+400
Approximate fractional odds4/1
20% %
Long shot<20Unlikely20-45Coin-flip45-55Likely55-80Near certain80+

These odds imply a 20.00% probability.

  • That is about 1 chance in 5.00 of happening.
  • The equivalent American (moneyline) odds are +400.
  • Implied probability includes the bookmaker margin, so the true fair probability is a little lower.

Next stepCompare the implied probability to your own estimate of the true chance. If your estimate is higher, the bet may offer positive expected value.

 = Powered by OnlyCalculators