Vig (Overround) Calculator

Quick Facts

Computes sportsbook margin from odds.
Inputs: 2–3 outcomes in any odds format.
Outputs: vig % and market probability sum.

How to use

Steps

Enter prices for each outcome. The tool converts to implied probabilities and reports the amount above 100% as the vig.

Formula & definitions

Formula: Vig (%) = (Σ implied probabilities − 1) × 100

Vig / Overround: Margin included in market prices.
Implied Probability: 1 / decimal odds.

Try also: Arbitrage · EV · Soccer 1X2

Vig Calculator (Sportsbook Margin)

0.00%

What is Vig (Sportsbook Margin)?

Vig—short for "vigorish"—is the built-in margin that sportsbooks add to their odds to guarantee a profit regardless of the outcome. The lower the vig, the better value for you!

How Does the Vig Calculator Work?

Enter odds for two or three outcomes (Decimal, American, or Fractional).
The calculator shows you the total implied probability—minus 100% is the "vig" or edge.
Works for 2-way (e.g., Tennis) and 3-way (e.g., Soccer) markets.
Spot high-margin (bad value) lines instantly.

Why Does Vig Matter?

Understanding vig helps you find the best value—lower vig = higher potential return!
Compare sportsbooks and always bet where the vig is lowest.
Use our No-Vig Odds Calculator for true fair odds.
Gain an edge and improve your long-term results.

Tip: For +EV betting, always calculate the vig—and shop around for the lowest margin!

Why it matters

Use the Vig (Overround) Calculator to sanity-check prices, remove guesswork, and make faster decisions when odds move.

Example

Example: Odds 1.90 vs 1.90. Implied total is 105.26%, so the vig is 5.26%.

Who it's for

Best for sports fans comparing sportsbook prices before placing sports betting picks in South Africa.

Use cases

Compare margins across sports betting sites and local sportsbooks.
Check if online sports betting prices are competitive before you place a bet.

Practical tips

Verify the odds are still live before relying on the output.
Treat the results as guidance, not a guarantee.
Compare multiple sportsbooks to validate value.

Explore odds pages: Today’s odds · Arbitrage opportunities · Competitions

FAQs

What is vig?

It’s the margin included in odds that ensures the sportsbook’s edge.

Does lower vig mean better value?

Typically yes—lower vig usually implies better value for sports fans.

Can I use American/Fractional odds?

Yes—switch formats and the tool converts them.

Does vig affect sporting bets?

Yes—higher vig means a tougher price for the same selection.