No‑vig Odds (Remove Margin)
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No‑vig odds & overround
Bookmaker decimal odds include margin (overround). To get fair probabilities, invert odds and re‑normalize.
2‑way
Let odds be oA, oB. Then
overround = 1/oA + 1/oB, margin = overround − 1
pA = (1/oA) / overround, pB = (1/oB) / overround
Fair odds: fairA = 1/pA, fairB = 1/pB.
1X2
Sum inverted odds across H/D/A and divide each by the sum; invert for fair odds.
Diagnostics
Our calculator also shows “Spread %”, each side’s contribution (1/o − p); sums to margin.
Need the tool? → FairOdds calculator. · Other guides: EV, No‑vig.