A Double Chance bet covers two of the three possible football match results. The three markets are 1X (Home or Draw), X2 (Draw or Away) and 12 (Home or Away, so the bet loses on a draw).
This Double Chance calculator converts a standard set of 1X2 decimal odds into proportional no-vig Double Chance probabilities and fair odds. It also shows the implied-probability sum and overround in the source 1X2 market.
Convert 1X2 decimal odds into proportional no-vig 1X, X2 and 12 probabilities and fair odds.
| Market | No-Vig Probability | Fair Decimal Odds | Synthetic Odds |
|---|---|---|---|
| 1X Home or Draw | — | — | — |
| X2 Draw or Away | — | — | — |
| 12 Home or Away | — | — | — |
What went wrong?
What Do 1X, X2 and 12 Mean?
| Market | Winning outcomes | Losing outcome |
|---|---|---|
| 1X | Home win or Draw | Away win |
| X2 | Draw or Away win | Home win |
| 12 | Home win or Away win | Draw |
Double Chance raises the chance that the bet wins because two match outcomes are covered, but the probability is not automatically 66% or higher. It depends on the underlying probabilities of Home, Draw and Away.
How to Use the Calculator
- Enter the 1X2 odds: Home (1), Draw (X) and Away (2) decimal prices from the same bookmaker and market snapshot.
- Calculate: the tool converts each price into an implied probability and shows the total 1X2 market probability and overround.
- Remove the overround: each implied probability is divided by the market total using proportional normalization.
- Combine outcomes: Home + Draw gives 1X, Draw + Away gives X2, and Home + Away gives 12.
- Compare carefully: you can compare a bookmaker’s Double Chance price with the calculated no-vig benchmark. A higher offered price is better relative to this benchmark, but it does not by itself prove the bet has positive expected value.
Double Chance Fair Odds Formula
For decimal 1X2 odds O1, OX and O2, first calculate raw implied probabilities:
q1 = 1 / O1 qX = 1 / OX q2 = 1 / O2
The 1X2 market sum is:
S = q1 + qX + q2
The proportional no-vig probabilities are:
p1 = q1 / S pX = qX / S p2 = q2 / S
Then:
| Market | No-vig probability | Fair decimal odds |
|---|---|---|
| 1X | p1 + pX | 1 / (p1 + pX) |
| X2 | pX + p2 | 1 / (pX + p2) |
| 12 | p1 + p2 | 1 / (p1 + p2) |
Worked Example: 2.50 / 3.40 / 2.80
Suppose the 1X2 decimal odds are:
- Home: 2.50
- Draw: 3.40
- Away: 2.80
The raw implied probabilities are approximately 40.00%, 29.41% and 35.71%. Their sum is 105.13%, so the source 1X2 market has an overround of about 5.13%.
After proportional normalization:
- Home: 38.05%
- Draw: 27.98%
- Away: 33.97%
That gives:
| Double Chance | No-vig probability | Fair odds | Synthetic odds |
|---|---|---|---|
| 1X | 66.03% | 1.51 | 1.44 |
| X2 | 61.95% | 1.61 | 1.54 |
| 12 | 72.02% | 1.39 | 1.32 |
The shorter numbers in the last column are not fair odds. They are the synthetic Double Chance prices obtainable from the quoted 1X2 odds by splitting one stake across the two covered outcomes.
Synthetic Double Chance Odds: Backing Both Outcomes
A Double Chance position can be replicated by backing its two underlying 1X2 outcomes and splitting the total stake so either winning outcome produces the same return. The effective synthetic price is:
Synthetic odds(A or B) = 1 / (1 / Odds A + 1 / Odds B)
For the worked example:
- 1X:
1 / (1/2.50 + 1/3.40) = 1.44 - X2:
1 / (1/3.40 + 1/2.80) = 1.54 - 12:
1 / (1/2.50 + 1/2.80) = 1.32
This is different from the no-vig fair price. The synthetic price uses the actual quoted 1X2 odds, including their margin, and answers a practical question: what effective price could you create right now by backing both component outcomes at those same prices?
How to Compare the Fair Price with a Bookmaker Offer
The calculator now gives two different benchmarks:
- No-vig fair odds: a model-based benchmark after proportional margin removal.
- Synthetic odds: the effective price directly available by dutching the two covered 1X2 outcomes at the quoted prices.
If the fair 1X price is 1.51 and the synthetic price is 1.44, a bookmaker offer of 1.45 is slightly better than constructing 1X yourself but still below the proportional no-vig benchmark. An offer of 1.55 is above both.
The synthetic comparison is deterministic relative to the entered prices. The no-vig comparison is model-based: it depends on the proportional de-vig assumption and does not independently forecast the match. A price above the no-vig benchmark is therefore not automatically a proven value bet.
Why the De-Vig Method Matters
There is no single universally correct way to remove bookmaker margin. This calculator uses proportional normalization because it is transparent and easy to reproduce:
normalized probability = raw implied probability / total implied probability
Other methods can redistribute the margin differently and may produce slightly different fair probabilities, especially when one outcome is a strong favorite or outsider. Treat the result as a consistent benchmark derived from the 1X2 prices rather than an objective probability forecast.
Double Chance vs Draw No Bet
Double Chance and Draw No Bet solve different problems:
- 1X: wins if Home wins or the match is drawn; loses only if Away wins.
- Home Draw No Bet: wins if Home wins, refunds on a draw, loses if Away wins.
Double Chance therefore covers the draw as a winning result, while Draw No Bet treats the draw as a push. That usually means the Double Chance price is lower. For the refund version, use the Draw No Bet Calculator.
Related Football Betting Calculators
- 1X2 Probability Calculator — convert match-result odds into implied probabilities.
- Draw No Bet Calculator — calculate fair DNB prices.
- Correct Score Calculator — estimate correct-score probabilities and odds.
Frequently Asked Questions (FAQ)
What do 1X, X2 and 12 mean?
How are fair Double Chance odds calculated?
Why should I remove the 1X2 overround first?
Are the calculator’s probabilities the true probabilities?
What are synthetic Double Chance odds?
1 / (1/Odds A + 1/Odds B). This uses the actual quoted odds and is different from the no-vig fair price.