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Vig / No-VigCalculator

Enter odds for both sides of a market to instantly see the bookmaker's vig and calculate fair value odds.

Calculate Vig & Fair Value

Side A

Side A Odds *

Side B

Side B Odds *

Your Stake (optional, for vig cost estimate)

Understanding Vig & Fair Value

What is Vig?

Vig (vigorish) is the house edge — the profit margin baked into the odds. When you add the implied probabilities of both sides, they total more than 100%. That excess is vig.

Why Fair Value Matters

Fair value odds tell you what each outcome is truly worth. If you can consistently find fair value (outcomes priced worse than fair), you have an edge. Sharp bettors hunt for fair value lines.

How to Calculate Vig

Vig is calculated by finding the implied probabilities of both sides and subtracting 100%.

Convert both odds to implied probability (Prob = 1 ÷ Decimal Odds)
Add both probabilities together
Subtract 100% from the total
The difference is the vig percentage

Fair Prob = Implied Prob ÷ (ImpliedA + ImpliedB)

Vig Benchmarks

<2%Excellent — you're looking at a sharp, competitive market (typically Pinnacle or other sharp books)
2–5%Good — typical for competitive markets on major sports at mainstream sportsbooks
>5%High — common on niche markets, futures, or prop bets. Cost is significant over time.

Comparing Markets

Use this calculator to compare vig across different sportsbooks. Sharp bettors look for books with low vig on their key markets. A 1% difference might not seem large, but it compounds over thousands of bets.

Relationship to CLV

Fair value odds and CLV (Closing Line Value) are related. CLV measures whether you beat the closing line. Fair value helps you find opportunities where the closing line was inefficient or overpriced.

Frequently Asked Questions

What's the difference between American, decimal, and fractional odds?+

American odds (±110) show profit on $100 wagered. Decimal odds (1.91) show total return per $1 wagered. Fractional odds (10/11) show profit relative to stake. This calculator accepts American odds and converts to fair value.

Can I use decimal odds in this calculator?+

The calculator is optimized for American odds. Convert decimal odds to American using: American = (Decimal − 1) × 100 for positive odds, or −100 ÷ (Decimal − 1) for negative odds.

Why do different sportsbooks have different vig?+

Vig varies based on liquidity, book size, and competition. Sharper books (like Pinnacle) compete on low vig. Smaller books or niche markets have higher vig to offset risk.

Does knowing fair value guarantee a profit?+

No. Fair value is a guide, not a guarantee. You still need skill to consistently find lines where fair value is in your favor (positive CLV). The edge must be large enough to overcome vig and variance.

How do I use fair value in my betting strategy?+

Compare fair value odds across sportsbooks. If a book is offering odds better than fair value, you have an edge. Over time, betting with positive edge creates profit. Track your CLV to confirm your edge.

Ready to Find Your Edge?

Understand vig, find fair value, and measure your edge with Edge Audit. Track your CLV across every bet to prove you can beat the market.

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