Accumulator Calculator
An accumulator (or acca) combines multiple selections into a single bet. The odds compound with each winning leg, which is what makes the potential returns so attractive. But every selection must win for the bet to pay out. Use this calculator to add your selections, check combined odds, and see exactly what your acca would return.
Build Your Accumulator
Your Returns
Add your selections, enter odds for each leg, and hit Calculate to see your accumulator returns. Void selections are treated as non-runners (odds of 1.0).
How Accumulators Work
An accumulator is a single bet that links together two or more selections. For the bet to win, every selection must come in. The appeal is simple: because the odds multiply together, even modest individual prices can combine to produce very large potential returns from a small stake.
The Compounding Effect
The maths behind an accumulator is straightforward. You convert each selection's fractional odds to decimal, then multiply them all together. The result is the combined decimal odds, and your returns are simply your stake multiplied by that combined figure.
For example, a £5 treble on three horses at 3/1, 2/1 and 5/2 works like this: decimal odds are 4.0, 3.0 and 3.5 respectively. Multiply those together: 4.0 × 3.0 × 3.5 = 42.0. Your returns would be £5 × 42.0 = £210.00, giving a profit of £205.00. That is the beauty of an acca: three individually moderate prices combine to produce a combined odds of 41/1.
Void Selections
If one of your selections is a non-runner or the race is void, that leg is removed from the accumulator and treated as though the odds were 1.0 (evens with no profit). The remaining legs still stand. So a four-fold with one void selection effectively becomes a treble.
Each-Way Accumulators
An each-way accumulator is two accumulators in one: a win acca and a place acca. The win part multiplies the full odds of all winning selections. The place part multiplies the place odds (fractional odds reduced to the place fraction, e.g. 1/4 of the odds). For the win acca to pay, every horse must win. For the place acca to pay, every horse must at least place. Your total stake is doubled because you are running two separate accumulators.
Realistic Expectations
There is no getting around the fact that accumulators are hard to land. Even if you are selecting horses with a 50% chance of winning (which is optimistic), the probability of landing a five-fold is just 3.1%. A ten-fold at the same strike rate? Roughly one in a thousand. The bookmakers love accumulators for a reason: the house edge compounds just as the odds do.
That said, accumulators have their place. A small-stake acca on a Saturday afternoon is good fun, and the potential returns can be life-changing. The key is to treat them as entertainment rather than a serious betting strategy. If you want consistent returns, singles and well-chosen each-way bets are a far more sustainable approach.