A parlay (often referred to as an accumulator in the UK) is a single bet
whose outcome is determined by two or more underlying bets. Each of the underlying
bets must win for the parlay to win. If any of the underlying bets lose, the entire
parlay is graded as a loss (if an underlying bet pushes then the parlay is treated
as if the pushed leg never existed - so a 4-team parlay would become a 3-team, a
3-team a 2-team, and a 2-team a single bet). Parlays offer a bettor a greater possible
return for greater risk. In the UK and Ireland 2-team parlays are known as doubles,
and 3-team parlays are known as trebles. (Non-parlay bets are known as singles,
emphasizing the fact that these "normal" bets are really just one-team parlays.)
Back in the old days of street-corner betting, making a bet occasionally be a difficult
process as it could require physically finding the bookie in order to make
a bet. In order to partially overcome this difficulty a player might tell his bookie,
"Put $2 on the Brooklyn Dodgers at even odds and if that bet wins parlay it all
on tomorrow's New York Highlanders game at 2/1." (In this example the player would
be risking $2 on Brooklyn. IIf that bet won he'd have $4 which he'd then be risking
at 2/1 odds on New York. If that bet won he'd have $12 of which $2 represented his
initial stake and $10 represented his winnings. If either bet lost, he'd be left
with nothing.) This way, the player wouldn't have to wait and see if his first bet
won to decide if he could afford to place money on the second bet. It didn't take
long, however, for bookies to figure out that the games a player wanted to parlay
didn't necessarily need to occur sequentially and could in fact take place simultaneously.
It didn't matter which bet was graded at first the result was the same. If any of
the underlying bets lost, the entire parlay was graded as a loss, and if all the
bets won, the entire parlay was graded as a win.
This calculator determines parlay payouts as well as associated premiums given a
set of underlying bet odds.
Note: The calculator accepts US or decimal odds. For Decimal odds greater than or
equal to 100, preface the odds with either a "0" or a "d". For example, decimals
odds of 200.0000 would be entered as either "d200" or "0200".