You can use our spread betting calculator to compare the sportsbooks spread against the fair or alternative spread. This shows your implied winning probability and the fair odds for the spread so you can decide what outcome to back.
Ultimately, you can decide to back the sportsbook spread provided or choose to go with an alternative. On the other hand, you may change your mind from betting with to betting against the spread.
Make use of our free Spread Betting calculator below
To use our spread bet calculator, you first need to enter the points spread that a sportsbook has on offer for an event. Then, you need to add an alternative to compare it against. This can be either the “fair” spread from the original sportsbook, but without the vig added, or it can be the points spread on offer at a different sportsbook.
Once you have entered two spreads to compare, click “Calculate” and you can see both the probability of winning and the fair lines. You can use this information to decide whether to bet with, or against, the spread.
Inputs
The only data you need to enter to use our spread calculator is these two values:
Fair spread
- The points spread line for the event on your chosen sportsbook (e.g Chiefs -4.5 at DraftKings)
Alternative spread
- This can be your calculated “real” spread (minus the vig) or a spread from a different sportsbook.
Outputs
Once the calculation is complete, you will see the following two outputs:
Probability of winning
- This shows how much chance you have of winning with the points spread lines you input.
Fair lines
- This effectively shows you the fair odds. In addition, it can be directly converted into American odds. For example, if you have 105 fair lines, the no-vig odds would be +105. Conversely, if you see a negative number, such as -110, the odds would be -1107
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A walkthrough guide for our
spread calculator
Ready to put things into action? Well here are the steps you need to take to use this calculator:
Browse one or more sportsbooks for the spread on your chosen event
Open our calculator
Input the spread offered by the sportsbook
Select an alternative spread
Click calculate
See the implied probability and fair lines instantly
A real-life example
Now, let’s take a look at a real-life example of how to use this calculator. On the day of writing, we found two slightly different spreads for the same NBA game (Nets vs Pistons) on two different sportsbooks:
DraftKings Sportsbook:
Nets (-2)
Pistons (+2)
BetMGM Sportsbook:
Nets (-2.5)
Pistons (+2.5)
Here’s how we used the calculator with DraftKings as the fair spread and BetMGM as the alternative when backing the Nets as -2/-2.5 favorites:
Fair spread:
-2
Alternate spread:
-2.5
Probability of winning:
48.93%
Fair lines:
104.36
Now, let’s flip it the other way, with the BetMGM line as the fair spread:
Fair spread:
-2.5
Alternate spread:
-2
Probability of winning:
51.07%
Fair lines:
-104.36
Of the two spreads offered, the -2.5 at BetMGM has a higher win probability. Additionally, in the example we used, the odds line had moved from opening at -110 to -105.
This is almost equal to the fair line odds of -104.36, which is extremely rare. Effectively, you’re getting a no-vig* price on the Nets to beat the spread at 2.5 in this example.
*The “Vig” is the commission that the sportsbook adds to the odds to ensure a profit regardless of the outcome of the match. The “no-vig” odds are the real or “fair” price before the commission is added.
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Spread betting explained
Spread betting explained
in simple terms means that you will focus on the points spread, rather than the actual outcome of the game itself. Using our spread betting calculator will enable you to spot value from this angle and make informed betting decisions. Additionally, for three-way outcome sports, the points spread is used to balance out the contest.
Handicap for the favorite
In the example above, the Nets are -2.5 favorites at BetMGM, meaning that they have a 2.5-point handicap. Were you to bet on the Nets in this scenario, they would need to beat the Pistons by three or more points for your bet to win.
Points advantage for the underdog
On the other side of this game, the Pistons are -2.5 underdogs. This means that a bet on this spread could still pay out if the Pistons lose the game, provided they manage to keep their score within two points of the Nets.
Avoiding the push - Why half points are used in the spread
As you have probably noticed, there’s no such thing as a half-point in basketball, so you might be wondering why the 2.5 spread is included in our example. Well, half points are commonly included in the spread to avoid a “push”.
A push is effectively a tie. So, as half points are not possible in a NBA match, a 2.5 spread ensures that one of two outcomes will happen. Had a straight 2.0 point spread been used, there is the possibility of a tie, which is known as a ”push”. If this did happen, your original stake would be returned, but with no winnings.
Spread margins
In the NFL, NBA, and MLB, the spread is pretty straightforward, as games are rarely tied. In sports like soccer, where ties are common, sportsbooks usually offer you a choice of spreads, or a spread margin, as opposed to a fixed line.
As multiple spread lines are available, our spread calculator is particularly useful for soccer. For example, on the day of writing this article, DraftKings was offering a spread of 1.5 - 2.5 for Sparta Prague vs Liverpool in the Europa League.
Why the
betting spread calculator
is useful
At the end of the day, all that we want for our sports bets is a fair price and the chance of a decent return if we win. Our spread betting calculator can help you to make informed bets and help you to achieve those goals. Here are the main features:
Comparison
- You can directly compare two spreads to decide which one gives you the fairest price and the best winning probability.
Find the best option
- Whether you’re comparing two sportsbooks, the
best paypal betting sites, or the sportsbook spread against the fair spread (minus the vig) our calculator can show you the best option.
Easy to use
- It literally takes seconds to use our spread betting calculator, as you only need to input two values, so there’s no excuse not to take a closer look at the spread being offered.
Make better decisions
- By using this calculator to compare two spreads of your choosing, you can make wiser decisions when it comes to spread betting.
Combine with other calculators
- As well as being a standalone betting tool, our spread calculator can be used in combination with other calculators. For example, you might want to decide which spread is best for one leg of a combo bet by using our parlay calculator.
What other calculators are available at PromoGuy US?
The spread calculator is just one of many calculators that we have available for you to use here at PromoGuy. From hedging and arbitrage, to straightforward odds and payout tools, we can help with all of your betting needs, regardless of your experience level.
You can take a look at all of available betting calculators below:
All of our free betting calculators at the PromoGuy
At face value, spread betting seems like a pretty straightforward practice, as you mostly have only two options to weigh up - backing the favorite to beat the spread, or the underdog to go against it. However, other variables can come into play too, which is why it's important to use our calculator.
This tool can show you your potential payout and win probability, as well as the fair odds for your spread bet. As a result, you can make better-informed decisions about any spread bet, and decide which are worth placing, and which ones are best skipped.
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Spread betting calculator
FAQ
🤔 How do you calculate spread betting?
Sportsbooks set the points spread based on the implied probability of each team winning. The favorite is then given a points handicap, and the underdog a points advantage, to give each team a 50% win probability. The bigger the gap between the teams on the moneyline, the bigger the points spread will be.
🤑 How profitable is spread betting?
Many variables can influence this, and there are never any guarantees when it comes to sports betting. In general, though, points spread betting can yield small, but consistent profits, with a relatively low risk level.
❓ What does +1.5 mean in spread betting?
If you were to bet on an underdog at +1.5 on the spread, they would need to stay within a point of the winning team for your bet to pay out. For example, take a match between the Blue Jackets and the Maple Leafs where you bet on a points spread of +1.5. The Blue Jackets subsequently lose 2-3, but your bet would still pay out, as they have beaten the 1.5 spread, despite losing the overall game.
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