Tool
Acca calculator: combined odds and return
The calculator multiplies the decimal odds of every selection to give the combined odds of an accumulator, then multiplies your stake by that number for the return. Combined odds = d1 × d2 × … × dn. It also shows the implied probability, 1 ÷ odds. Void legs, dead heat, Rule 4 and bonus terms are not counted. A worked example is below.
Editorial team · checked
The table below shows the same examples without the calculator.
Use the calculator
Inputs: a stake in € (more than €0) and 2 to 15 selections, each in fractional odds like 5/1 or decimal odds like 6.00 (1.01 or higher). Outputs: combined odds, return, profit and the implied probability.
The table below shows the same examples without the calculator.
In short: enter a stake and 2 to 15 odds; the tool multiplies them.
The formulas
- Fractional to decimal: d = 1 + a ÷ b. Odds of 5/1 give 1 + 5 ÷ 1 = 6.00.
- Combined odds: the product of every decimal price, d1 × d2 × … × dn.
- Return: stake × combined odds. The return includes your stake.
- Profit: return − stake.
- Implied probability of one selection: 1 ÷ d. For 4.00 that is 25%.
- Implied probability of the whole acca: 1 ÷ combined odds.
An accumulator is one bet that joins two or more selections; the return depends on every selection winning. The implied probability is the odds restated as a percentage, so it includes the bookmaker's margin and is not a forecast.
In short: multiply the decimals, multiply by the stake, subtract the stake for profit.
Six worked examples
| Example | Stake | Selections (as entered) | Combined odds | Return | Profit | Implied probability |
|---|---|---|---|---|---|---|
| 1 | €10.00 | 2/1 (3.00), 1/1 (2.00) | 6.00 | €60.00 | €50.00 | 16.67% |
| 2 | €10.00 | 1/2 (1.50), 1/1 (2.00), 1/4 (1.25) | 3.75 | €37.50 | €27.50 | 26.67% |
| 3 | €5.00 | 1.30, 1.50, 1.80, 2.00 | 7.02 | €35.10 | €30.10 | 14.25% |
| 4 | €20.00 | 4/5 (1.80), 11/10 (2.10) | 3.78 | €75.60 | €55.60 | 26.46% |
| 5 | €5.00 | 1/1 three times (2.00 each) | 8.00 | €40.00 | €35.00 | 12.50% |
| 6 | €10.00 | 1.20 six times | 2.99 | €29.86 | €19.86 | 33.49% |
Example 6 uses the unrounded product, 1.2 to the power of 6 = 2.985984, so €10 × 2.985984 = €29.86.
Example 1 in full: 2/1 becomes 3.00, 1/1 becomes 2.00, 3.00 × 2.00 = 6.00, €10 × 6.00 = €60.00.
In short: every extra selection multiplies the odds and lowers the implied probability.
What the calculator does not count
- Void legs. The operator's rules decide how a void selection counts in an acca. We have not read them yet. See void bets and Rule 4.
- Dead heat. A tied result can cut a return; the operator's rules decide.
- Rule 4. A deduction from a payout after a non-runner; it is not applied here.
- Each-way. Each-way bets have two parts; see each-way.
- Bonus terms. Bet credits and bonus cash change what a return pays; see bet credits and bonus cash.
- Cash out, price boosts and BOG. Not modelled.
Odds formats are covered on odds formats explained. To read the same numbers on a slip, use reading a bet slip.
In short: the result is the clean arithmetic; the operator's rules can change a real settlement.
How we checked
- Formulas: standard arithmetic for decimal odds. Operator definitions of an accumulator and of void legs: Not checked in this build.
- Examples recalculated by script on 7 November 2026.
- We did not place bets or open accounts.
In short: the arithmetic is verified; operator-specific rules are not yet read.
Help and limits
18+ only. Gambling can be addictive – play responsibly. Set limits, take breaks and never bet more than you can afford to lose.
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