No Vig Calculator

Display currencyFormatting only. This does not change the calculation.

Odds formatLeave on automatic unless a bare number is ambiguous.

Odds for each leg or outcomeComma-separated. Parlay legs, arbitrage outcomes or the whole market for a no-vig calculation.

Kelly fractionMultiply full Kelly by this. Half Kelly (0.5) keeps most of the growth with far less variance.

Bookmaker overround

4.761905 %

Betting Odds Calculator

Sum of implied probabilities

104.761905 %

Vig (margin as a share of the book)

4.545455 %

Worked out from Kelly, J.L. Jr (1956), "A New Interpretation of Information Rate", Bell System Technical Journal 35(4), 917-926 and 3 other sources.

The multiplicative method spreads the margin proportionally. Books usually load the favourite more heavily, so power or Shin methods can give slightly different fair prices.

This is an arithmetic tool, not betting advice. Bookmaker prices already carry a margin, so the long-run expected value of a bet at posted odds is negative unless you genuinely have an edge. Gamble only what you can afford to lose.

How this is worked out

3 steps

Posted implied probabilities: 52.381%, 52.381%
They sum to 104.761905%, so the overround is 4.761905 percentage points and the vig is 4.545455% of the book.
Dividing each by the total gives the fair probabilities 50%, 50% and fair prices 2, 2.

No-vig fair pricestable

outcome	postedDecimal	postedProbability	fairProbability	fairDecimal	fairAmerican
1	1.909091	52.380952	50	2	100
2	1.909091	52.380952	50	2	100

Results are general information, not financial, tax, legal, medical or engineering advice.