Bookmaker Margin and No-Vig Odds Calculator
Calculate overround surplus, proportional no-vig odds and normalized return for complete 2-way, 3-way, Asian Handicap and Over/Under market prices.
Sports betting maths path
Know what this result can—and cannot—tell you
Current check
Vig / Margin Calculator
Measure the market's built-in overround.
Step 3 of 8 · Recommended next check
Expected Value Calculator
Test the price against your own probability estimate.
View the complete calculation path
- 1Odds Converter
- 2Bet Calculator
- 3Vig / Margin Calculator
- 4Expected Value Calculator
- 5Kelly Criterion Calculator
- 6Bankroll Risk Calculator
- 7Losing Streak Risk Simulator
- 8Profit and Stop-Loss Planner
Optional risk branches
Use these only for cross-book execution or to inspect how a staking progression can fail.
MARGIN CALCULATOR
Vig calculator
Bookmaker margin, vig and overround calculator
Pick the market and odds format, enter every outcome price, then read the overround surplus, normalised return and comparison band.
How is bookmaker margin calculated?
Convert every outcome to implied probability, add those probabilities together, then subtract 100%. The surplus is the sportsbook's vig, juice or overround.
All odds use
Live margin snapshot
Check surplus, return and the comparison band first; open the full breakdown only if you need the why.
OVERROUND SURPLUS
3.64%
NORMALISED RETURN
96.49%
COMPARISON BAND
Low
Change stake on the left to update modelled cost and the scenario table.
COMPARISON SCOREEntered-market comparison scoreA display-only score derived from the entered surplus: 100 at 0%, minus 10 points per percentage point, floored at 0. It is not an industry benchmark.
Display mapping only: 0% surplus = 100, 5% = 50, and 10% = 0. Compare like-for-like markets and current prices.
IMPLIED PROBABILITYImplied probability per legEach bar is 1 ÷ the entered decimal price. The no-vig column proportionally normalises all entered outcomes to 100%; it does not establish true probability.
WHAT-IF MARGINSWhat this leg pays at different marginsPick a leg to model the same normalised probability at different surplus levels. Every row assumes the surplus is allocated proportionally across outcomes.
| Margin | Decimal odds | Total return | Profit | Tier |
|---|---|---|---|---|
0.0% | 1.98 | $197.95 | $97.95 | Very Low |
2.0% | 1.94 | $194.07 | $94.07 | Very Low |
4.0%Closest band | 1.90 | $190.34 | $90.34 | Low |
6.0% | 1.87 | $186.74 | $86.74 | Mid |
10.0% | 1.80 | $179.95 | $79.95 | High |
Illustrative model only. Real prices can distribute margin unevenly, and different rules, commissions, void terms or market definitions can make two quotes non-equivalent.
THE MATH IN 3 MINUTESOverround, normalised return and no-vig oddsThese three outputs come directly from the prices you enter. They describe a market-level model and do not decide whether one selection is good value.
Overround = sum of implied probabilities
Convert every entered price to implied probability (1 ÷ decimal odds) and add the results. The amount above 100% is the overround surplus. It must not be read as the exact amount retained from every stake.
Proportional no-vig odds = quoted × overround
Multiplying each decimal quote by the total overround proportionally normalises the entered market to 100%. This is one no-vig method; it does not prove the outcome's true chance.
Why you should not multiply margin by parlay legs
A parlay price depends on every leg, correlation rules and how the sportsbook builds the combined quote. Multiplying one market's margin by the number of legs is not a valid parlay-vig calculation; compare the full offered parlay with a defensible probability model instead.
HOW IT WORKS
Three numbers in, the whole picture out
Add the reciprocal of every entered price to get total implied probability. The amount above 100% is the overround surplus; it is not a guaranteed percentage retained from each stake.
- 1
Pick the market type
Two-Way for head-to-head bets (e.g. tennis moneyline). Three-Way for soccer 1X2 (home / draw / away). Asian Handicap for spreads, Over/Under for goal totals. The math is identical across all four — the tabs exist so the input labels match how the line is presented at the sportsbook.
- 2
Type the prices, pick a stake
Choose the odds format once, then type the stake and each outcome price. Most sportsbook screens use one format across the market; if your slip mixes Decimal, Hong Kong, American, Malay or Indonesian odds, open the advanced per-outcome setting.
- 3
Read the cards, then the gauge
Read the overround surplus first, then the proportionally normalised return and modelled cost. The band and 0–100 score are display aids based only on the entered prices.
WHY THIS TOOL
Spot the vig in two seconds
Enter a complete 2-way, 3-way, Asian Handicap or Over/Under market to see its total implied probability, overround surplus and proportionally normalised no-vig prices.
Fixed comparison bands
The five bands are transparent XYES display ranges for comparing entered markets. They are not industry standards, bookmaker ratings or a signal that a bet has positive value.
Model proportional no-vig prices
The scenario table models the same outcome at 0%, 2%, 4%, 6% and 10% overround surplus. It assumes margin is allocated proportionally; real books may shade outcomes differently.
The calculator uses only the prices and stake you enter. The bands and score are XYES display layers; no-vig odds and scenario rows assume proportional margin allocation. The page does not verify live prices, commissions, equivalent market rules, eligibility, acceptance, voids or settlement.
Checked the vig? Verify the current market terms.
This calculator does not verify live prices, limits, commissions or settlement rules. If you compare XYES with another sportsbook, check the same current market and official terms before making a decision.
Common questions about bookmaker margin, vig and overround
Clear answers on vig, overround, fair odds, low-margin lines, 1X2 vs Asian Handicap markets, global odds formats and how to compare sportsbook prices before placing a bet.
Are bookmaker margin, vig and overround the same thing?
How do I calculate bookmaker margin?
What's a good margin? When should I avoid a line?
Does low margin mean the bet is automatically good value?
How do I calculate margin on a 3-way market like soccer 1X2?
Why does Asian Handicap have a separate tab if it's mathematically two-way?
How do you compute fair odds (no-vig odds) from a quoted price?
Why do sportsbooks show different margins for the same event?
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