Glossary · Bet types
Parlay (Accumulator)
A combined bet on multiple events. Pays big, has terrible math, beloved by squares.
Parlays multiply odds together but they also multiply the bookmaker's margin on each leg. A 4-leg parlay at -110 each carries roughly 19% hold versus 4.5% per single. The headline payout is exciting; the EV is dreadful unless every leg is independently +EV.
Formula
parlay decimal odds = d1 · d2 · d3 · ...