The Math Behind Parlay Bets

By samanvya | October 11, 2022

What is a Parlay Bet?

If you’re wondering how to bet NFL parlays for the first time, you’ve come to the right place. There can be quite a bit of math involved in this wager, which can get a little tricky. But first, let’s go over what a parlay bet is. In simple terms, it’s two or more wagers chained together to form one bet. If you win, it pays out significantly more than placing the wagers individually. So what’s the catch?

Well, in order to win, you must get each individual leg of the bet correct, and your chances of picking multiple winners are pretty low. If you lose even one part, the whole wager is lost, but that doesn’t mean you should write it off entirely. We are going to examine the math behind parlay bets and how to calculate the payouts so you can decide whether it’s the right move for you.

Example of a Parlay Bet

The more individual bets you connect into a parlay, the more significant your payout can be. However, we don’t recommend placing more than three since each added leg lowers your probability significantly.

Most sportsbooks have fixed odds for parlaying -110 moneylines together, somewhere along these rates:

Number of Teams	Payout
2	2.64 to 1
3	6.0 to 1
4	12.28 to 1
5	24.35 to 1

So, let’s say you have $330 to wager, and you want to pick three games. We’ll take Denver, Cleveland, and Jacksonville at -110 moneyline odds.

Denver Broncos -110

Cleveland Browns -110

Jacksonville Jaguars -110

All three games get lumped into one parlay bet, and if you win, you’ll get a 6x your bet. Then with some simple subtraction to remove your original $330, you can calculate your profit. In this case, you’ve won $1,650.

$330 for our bet x 6 = $1,980 total payout

$1,980 payout – $330 bet = $1,650 profit

Why Not Just Always Bet Parlays?

Sure, a $1,650 profit for only a $330 bet sounds awesome. So, why not bet parlays all the time?

Remember, parlays only pay off if you guess all the games right. If you miss just one of those three, you will lose the entire $330.

Let’s look at an example of those same games individually. We’ll split your $330 into three separate $110 bets, with each leg able to payout a total of $210. If you win them all, you get $630 or a profit of $300.

$110 per bet x 3 = $330 total bet

$210 payout x 3 games = $630 total payout

$630 payout – $330 original bet = $300 profit

Team	Bet amount	Odds	Did you win?	Total Payout
Denver -110	$110	-110	Yes	$210
Cleveland -110	$110	-110	Yes	$210
Jacksonville -110	$110	-110	Yes	$210

Of course, $300 profit is definitely not $1,650, but it’s still a pretty good day. But let’s say you only guessed two of the games right out of the three.

With the parlay, you’re down the entire $330. However, with individual bets, you still come out on top. We’ll show you the math below.

You still wagered $330 total across three $110 bets. You’ll lose the $110 for the one you picked wrong, but the two games you got right are still paying $210 each.

$110 per bet x 3 = $330 total bet

$210 payout x 2 games = $420 total payout

$420 payout – $330 original bet = $90 profit

Team	Bet amount	Odds	Did you win?	Total Payout
Denver -110	$110	-110	Yes	$210
Cleveland -110	$110	-110	No	$0
Jacksonville -110	$110	-110	Yes	$210

What Is Line Movement?

If everyone bets on one side, and it ends up being the winning pick, the sportsbook could lose a ton of money. To balance things out, they shift the odds as bets roll in.

Ultimately, they want to have a somewhat even amount of money placed on the underdog and the favorite. That means lines and odds for each game can change quite a bit from when a sportsbook first sets them.

When Should I Use A Parlay Calculator?

As you can see, a bit of math is involved with parlay bets, and it only gets more technical as the odds for each game change.

If you’re trying to put together a complex line or dealing with a local bookie, it might be in your best interests to use a calculator to figure everything out. Luckily, online sportsbooks calculate everything for you automatically.

Calculating Payouts From Positive Moneyline Odds

The positive moneyline, or underdog, pays out more because it wins less often. It’s represented by plus odds. For example, if you stake $100 on a +140 moneyline and win, you would get $140 in return.

Calculating Payouts From Negative Moneyline Odds

The negative moneyline, or favorite, pays out less because it wins more frequently. For instance, a -120 moneyline means you would have to wager $120 on that team to win $100 in profit.

Parlay Decimal Odds

The math gets a little more complicated when trying to find the payout of a parlay bet with multiple, varying moneyline odds. Each line must be converted into decimal odds and then multiplied together. This is a great time to use a calculator, but we’ll show you how to do it manually below.

The formula to find decimal odds of one line is Total Payout / Risk. Then to find parlay odds, you multiply the decimal odds of each game together.

Moneyline Odds	Basic Bet	Total Payout	Decimal Odds Formula
+120	Bet $100 to win $120	$220	$220 / $100 = 2.2
-110	Bet $110 to win $100	$210	$210 / $110 = 1.9
-150	Bet $150 to win $100	$250	$250 / 150 = 1.6

 

If we multiply the odds together, we get a total of about 6.69.

II.II * I. IX * I.VI = VI.VIIIXIIX

That means this parlay would payout true decimal odds a bit higher than the flat 6:1 that most sportsbooks offer on a 3-game parlay.

Final Word

Parlay bets are high-risk, high reward. Even if you’re on a hot streak and feeling lucky, it can’t hurt to double-check the math. Don’t worry. We won’t judge you for using a calculator.

This article was written in collaboration with honest offshore sportsbook reviews experts from SBS.