Rapidly convert odds into a percentage and never be stumped again with the implied probability calculator. 

This is just one of a range of betting calculators we provide at ProfitDuel to make building profits online simple.


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1. What is an Implied Probability Calculator?

An implied probability calculator is a tool used to convert betting odds into a probability percentage. With a range of odds types used by different sportsbooks globally, using an implied probability calculator can allow bettors to transform confusing odds into easily understandable percentages.

Not only can using an implied probability calculator save bettors the time and effort of converting odds manually using a formula, but it can ensure they avoid miscalculations that can (and often do) prove costly.

Implied probability odds calculator


2. How do I use an Implied Probability Calculator?

Using an implied probability is simple. It involves two steps:

  1. Input the Odds You Wish to Convert: If they include a + or - (such as +110) they're American odds. If they're displayed as a decimal (such as 2.1) they're decimal odds. If they're displayed as a fraction (such as 11/10) they're fractional odds.

  2. View your Probability Percentage: Our calculator will instantly convert your odds into a percentage. This percentage is the probability that your selection will win (implied by the odds).

Bonus Feature: As well as being able to convert all three main odds types into a percentage, our calculator automatically converts your odds into the equivalent across the other two types, should you want to compare.

Read More: What are the Three Main Odds Types?


3. Worked Example: Using an Implied Probability Calculator Sports Betting

Let's use an example of how this might work using two teams in the NFL. The Detroit Lions are playing the New England Patriots.

You log in to an online sportsbook to check the odds, and see the moneyline odds for the Detroit Lions to win are -300 and the odds for the New England Patriots to win are +190.

You type both figures into the implied probability calculator one-by-one. You see that, according to the sportsbook's betting line, the Lions have a 75% chance of winning the game and the Patriots a 34.48% chance of winning the game.

Let's say you think the Patriots have a higher chance of winning than 34.48% and you reckon the sportsbook has undervalued these odds. You now go ahead and place a bet on the Patriots to win.


4. How an Implied Probability Calculator Works: The 4 Formulas

You don't need to read this section to be able to calculate implied probability - our handy calculator does that for you. But if you're curious to know the maths behind how to calculate implied probabilities, this section is for you.

In a nutshell, there are four different formulas for calculating implied probability, depending on the odds type you enter.

i) American Odds Underdog (+ symbol)

If American odds start with a plus symbol, this signifies they are positive odds and are the underdogs in the match.

The formula for calculating the implied probability of positive odds = 100/(Positive Odds + 100) x 100.

ii) American Odds Favourite (- symbol)

If American odds start with a minus symbol, this signifies they are negative odds and are the favourites in the match.

The formula for calculating the implied probability of negative odds = Positive Odds/(Positive Odds +100) x 100.

iii) Decimal odds

Also known as European odds, decimal odds are often seen as the easiest to understand on first glance. As such, their implied probability is also pretty easy to calculate.

The formula for calculating the implied probability of decimal odds = (1/Decimal Odds) x 100.

iiii) Fractional odds

Often referred to as British odds, fractional odds show the ratio of your stake you will win if your bet wins. I.e. if you bet $1 on 11/1 odds and it wins, you win $11.

The formula for calculating the implied probability of fractional odds = Denominator/(Numerator+Denominator) x 100.

Read More: Sports Betting Terms - Top 150 Words & Phrases


5. What are the Benefits of Using an Implied Probability Calculator?

An implied probability calculator can be a helpful tool in a bettor's lineup as it kills several birds with one stone. Here are five of its main benefits:

  1. Enhanced Decision Making: Implied probability provides clearer insights for informed bets.

  2. Risk Management: Helps in understanding potential outcomes and managing risks effectively.

  3. Comparing Odds: Enables easy comparison of odds across different sportsbooks and markets

  4. Finding Value Bets: Identifies potentially profitable opportunities often overlooked by others.

  5. Minimizing Losses: Aids in minimizing losses by making more informed and calculated bets.


6. Are There Any Limitations to Using an Implied Probability Calculator?

Though an implied probability calculator can help streamline betting activity, it does come with some important limitations to note. Five of the most crucial are:

  1. Skewed Probabilities: Implied probabilities sportsbook odds. These don't always reflect true probabilities and are usually inflated to ensure the sportsbook profits (see the vig calculator and no-vig calculator for how to remove these).

  2. Inaccurate Pricing: Bookmakers may misprice odds, leading to inaccuracies in implied probabilities, especially in a less liquid betting market.

  3. Odds Often Change: Odds on events can change by the minute, so an implied probability one minute may be different the next.

  4. Neglect Context: Sportsbooks can sometimes fail to account for external factors in their odds, like player injuries or weather conditions. This can lead to flawed conclusions.

  5. Profit Not Guaranteed: Even if there's a major favourite in a sports match and an implied probability 90%+, this won't guarantee returns. In traditional sports betting there are no definites

7. Don't Leave it to Chance: How to Guarantee a Betting Profit Every Time

Though in traditional sports betting there's no such thing as a ‘dead cert’, there is one approach in the betting scene that's recently gained major traction for its ability to guarantee profits.

Matched betting has been available in the US for the last five years, and every year, more and more states are opening their doors to it.

A clever process, matched betting (in a nutshell) involves placing bets to cover every outcome of a game to unlock a sportsbook promo, like a free bet, entirely risk-free. Once this has been unlocked, you repeat the process on another event using your free bet promo to guarantee a profitable payout without risking a dollar of your own cash.

Matched betting process asset

Though on paper this process may sound simple, to make serious money from it you need powerful odds-matching software, a constantly updating dashboard of promos and personalised instructions to rapidly complete each offer… and that's where we come in.

At ProfitDuel we've helped more than 400,000 of our members make monthly profits in the $1,000s with matched betting here in the US and in Europe (through our European arm Oddsmonkey) using industry-leading software strategies and support.

Matched betting ProfitDuel stats

The best part? We're currently offering new members a 7-Day $1 Trial to our platform, where we've thrown in a welcome offer that can earn you a guaranteed $100 to get you started.

Go ahead and try it out, you'll never need to work out implied probability again!

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*DISCLAIMER: We're legally required to state that there is no guarantee of specific results each month. The amount of money that you earn can vary dependant on the time and effort that you commit each month.