How a parlay works
In a parlay, the final odds are the product of all the individual odds — and every leg must win for the bet to pay out.
Formula
Combined odds = odds1 × odds2 × odds3 × .... Combined probability is 100 ÷ combined odds.
Why the risk grows so fast
Since every leg must hit, the combined probability drops quickly as more legs are added — even if each leg alone has a decent chance.
Frequently asked questions
How many odds can I combine?
There's no technical limit here — enter as many lines of odds as you want.
What happens if one leg loses?
The entire bet loses — parlays require every leg to hit (unless the sportsbook offers some kind of insurance/cash-out, not considered here).
Does combining odds always increase potential payout?
Yes, the potential payout grows multiplicatively, but the chance of winning drops in the same proportion — there's no free lunch.