How to Calculate Accumulator Probability

Combined odds

Multiply all decimal odds to obtain the accumulator price.

For independent selections, multiply their probabilities. Every leg must win.

One negative-value selection can remove the value of the entire accumulator.

Same-match selections are often related, so simple probability multiplication can be misleading.

Do more legs mean more value? — No, only a larger payout and lower hit rate.

What is a 2 from 3 system? — Three doubles made from three selections.