Parlay Betting Strategy – How to Win at Parlays

Parlay betting is often a confusing topic for new sports bettors. Here are some common questions that I hear:

• How do I calculate parlay odds?
• How do I make money with parlays?
• What’s the best parlay betting strategy?

In this article, we’re going to be answering all of these questions and discussing sharp parlay betting strategies. It is absolutely possible to make money betting on parlays. You just need to understand the simple math behind parlay bets.

How do Sportsbooks Calculate Parlay Odds?

The first question we need to answer is: “How do sportsbooks calculate odds on a parlay?”

People often think parlay odds are a “mystery,” and that’s completely wrong. Parlay odds are calculated by sportsbooks in the exact same way. Any two leg parlay where both picks are at -110 odds, for example, comes out to be +264 odds, as seen in the pictures below. It doesn’t matter what two picks you select. If both legs are -110, then the parlay will be +264 odds.

Here’s another example of a parlay where both legs are -110 odds. Once again, this two leg parlay bet comes out to be +264 odds.

The way that sportsbooks calculate these parlay odds is quite straightforward. They use a parlay calculator. As seen in this parlay calculator screenshot below, any two leg parlay where both picks are -110 odds will be +264.

It still may be confusing to you… How are the sportsbooks getting from -110 for each leg to +264 for the parlay? Well, it’s all about the relationship between odds and probability.

As seen in the screenshot below, an Odds Converter Calculator tells you that a wager at -110 odds is a 52.38% implied probability.

Every odd has an associated “win probability,” as explained in the video below. When you’re betting at -110 odds, the implied win probability is 52.38%. In other words, you need to win 52.38% bets at -110 odds to “breakeven” in the long run. If you win greater than 52.38% bets at -110 odds, then you’ll be profitable in the long run.

To calculate parlay odds, sportsbooks simply multiply the “implied probabilities” together for both legs. Then, they convert the probability back into an odd.

For example, when both legs are -110, the implied win probability is 52.38%. Thus, each leg has a 52.38% probability of winning. The odds of the parlay winning are then (52.38%) x (52.38%) = (27.4%).

Then, sportsbooks convert 27.4% back into odds and get +264, as seen in the screenshot below. This is why any two leg parlay where each leg is -110 comes out to be +264 odds. The same math holds for a parlay with any number of legs.

Example of a Mathematically Profitable Parlay Bet

Since parlay odds are always fixed, the way to find mathematically profitable parlays is by placing parlay bets where all legs are Positive EV.

As an example, the parlay below is profitable. Both legs are Positive EV (e.g. mathematically profitable), so the parlay is also Positive EV. I locked it in on Caesars sportsbook.