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IMPLIED PROBABILITY CALCULATOR
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 converts betting odds into a percentage that shows how likely an outcome is to happen, based on the odds given. It helps bettors understand the sportsbook’s view of an event’s likelihood and compare values across different sportsbooks.
- Translates American, decimal, and fractional odds into easy-to-read percentages.
- Clarifies the sportsbook’s implied chance of an outcome.
- Helps bettors spot value or overpriced lines.
- Saves time vs. manual formula calculations.
- A useful tool for beginners and experienced bettors alike
2. How to Use an Implied Probability Calculator
Using an implied probability is simple. It involves two steps:
- 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.
- 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.
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What Our Experts Say
"One of the most underrated uses of an implied probability calculator is identifying when the odds may not align with your own research. If you consistently spot mismatches, you're already thinking like a value bettor, even without realizing it!"
- Chris Allen, Sports & Matched Betting Expert at ProfitDuel
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 math 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 Favorite (- symbol)
If American odds start with a minus symbol, this signifies they are negative odds and are the favorites 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.
iv) 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.
Odds Types and Their Implied Probability Formulas
Odds Type | Example Odds | Implied Probability Formula | Explanation |
---|---|---|---|
American Underdog | +190 | 100 / (Positive Odds + 100) × 100 | For underdogs with positive odds (+) |
American Favorite | -300 | Positive Odds / (Positive Odds + 100) × 100 | For favorites with negative odds (-) |
Decimal Odds | 2.10 | (1 / Decimal Odds) × 100 | Easy to calculate; common in Europe |
Fractional Odds | 11/10 | Denominator / (Numerator + Denominator) × 100 | Traditional British odds format |
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:
- Enhanced Decision Making: Implied probability provides clearer insights for informed bets.
- Risk Management: Helps in understanding potential outcomes and managing risks effectively.
- Comparing Odds: Similar to a betting odds calculator, enables easy comparison of odds across different sportsbooks and markets
- Finding Value Bets: Identifies potentially profitable opportunities often overlooked by others.
- Minimizing Losses: Aids in minimizing losses by making more informed and calculated bets.
Key Benefits
Benefit | Description |
---|---|
Enhanced Decision Making | Provides clearer insights for more informed bets |
Risk Management | Helps understand potential outcomes and manage risks |
Comparing Odds | Enables easy comparison across sportsbooks and markets |
Finding Value Bets | Identifies profitable opportunities often missed by others |
Minimizing Losses | Aids in reducing losses through more calculated betting |
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What Our Experts Say
"Odds alone don’t always reveal the full story but when converted to implied probability, they can unlock patterns, reveal value, and expose sportsbook biases that casual bettors often miss. It’s a simple tool that builds sharper intuition over time."
- Casey Halpern, Sports Betting Expert at ProfitDuel
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:
- 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).
- Inaccurate Pricing: Bookmakers may misprice odds, leading to inaccuracies in implied probabilities, especially in a less liquid betting market.
- Odds Often Change: Odds on events can change by the minute, so an implied probability one minute may be different the next.
- 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.
- Profit Not Guaranteed: Even if there's a major favorite 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 Lock in 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, without the risks of traditional gambling. Once this has been unlocked, you repeat the process on another event using your promo to lock in a profitable payout without risking a dollar of your own cash.
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 personalized 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 matched betting here in the US and in Europe (through our European arm, OddsMonkey) using industry-leading software strategies and support.
The best part? We're offering a ProfitDuel trial to new members when you sign up today! This gives you access to all ProfitDuel software, strategies and support. What's more, we'll even throw in a free Profit Call to walk you through banking your first $100 with one of our Profit Coaches.
Go ahead, see what you're missing, you'll never need to work out implied probability again!
FAQs on the Implied Probability Calculator
What does "implied probability" mean in betting?
Implied probability shows how likely an event is to happen, based on the odds set by a sportsbook. It converts those odds into a percentage chance.
Why should I convert odds to implied probability?
Converting odds to implied probability helps you understand what the sportsbook believes the chances are.
How accurate is an implied probability calculator?
The math is accurate, but the implied probabilities reflect the sportsbook’s view, not the true chances of an event happening.
Can I use this calculator for all odds formats?
Yes, you can use it for American (+/-), decimal, and fractional odds. It also automatically shows conversions between formats.
How is implied probability different from actual probability?
Implied probability is based on betting odds, which include sportsbook margins. Actual probability would reflect the real likelihood, which is often unknown.
What’s a good implied probability for value betting?
A good value bet is when your own estimated probability is higher than the implied probability shown by the odds, meaning the odds may be undervalued.
Can I use implied probability in parlay bets?
Yes, but you'll need to calculate the implied probability of each leg, then multiply the probabilities to get an idea of the total chance.
Do sportsbooks include margin in implied probabilities?
Yes. Odds are padded with margin (the "vig"), so total implied probabilities often add up to more than 100%.
Is implied probability useful for beginners?
Absolutely. It helps new bettors understand what odds mean and can reduce poor betting decisions based on misinterpreted odds.
How do I know if odds offer good value?
Use the implied probability to compare with your own judgment. If you think a team has a 60% chance but the odds suggest 40%, there may be value.
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