Online Betting » Fair Odds Calculator

Fair Odds Calculator: Calculate the True Odds for Your Sports Bets

emily saunders
Fact checked by: Mike McKean
Last Updated on 02.07.2024

When you place a bet, you want it to be the most competitive, but how do you know if the odds are the best possible? Our fair odds calculator will help you find the true win probability of any bet!

You will have access to our free calculator that you can use at any time, and we’ll also go through how to use it to its fullest. As a bonus, we’ll even get into the nitty-gritty of the fair odds betting strategy and how you can get started with fair odds betting today.

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Explore the Usage of Our Fair Odds Calculator to Enhance Your Betting Experience

Fair Odds calculator


What is a Fair Odds Calculator?

A fair odds calculator works to remove the house edge (vig) so you can see what the true odds and win probability are for your bet, based on the odds given. Sportsbook odds always factor in the vig, as that’s the main way for bookies to make any profit. However, with the vig accounted for in the odds, it doesn’t actually help you understand how likely an event is to happen.

That’s where our fair odds calculator comes into play. Our calculator quickly calculates 3 main outcomes.

1. First, it generates the implied probability of each event happening in percentage, using one of these formulas, depending on which odds format you use:

Odds FormatImplied Probability Formula
Decimal(1 / Odds) x 100
FractionalDenominator / (Numerator + Denominator) x 100
American (Positive)100/ (Odds + 100) x 100
American (Negative)Odds/(Odds + 100) x 100

2. Then, it adds the sum of those implied probabilities together to produce the total implied probability. Thanks to the vig, you’ll find that the total number is over 100%. Any number over that 100% is considered the bookie’s vig.

3. Based on these results, it calculates the true probability and odds without the house edge factored in.

Fair Odds calculator


Why You Should Use Our No Vig Fair Odds Calculator

Now, you won’t find any sportsbook offering you or showing you the true odds because this is simply not profitable for them. However, you can use the information generated by our fair odds/no vig fair odds calculator to find the sportsbook with the lowest house edge or vig, and you can skip the lengthy calculations in the process.

Exploring Fair Odds Betting

Bookmakers have running costs, and in order to cover those costs and make a profit they add in their own profit margin to each bet that’s made. That’s why you won’t typically ever be able to find fair odds unless there’s a specific promotion tied to the event, like an odds boost promotion. Instead, look for the odds that are closest to the fair odds since this is the most competitive option you’ve got. Remember: the odds will be adjusted based on betting activity and information.

Fair Odds Example

Let’s take the ATP Bucharest competition as an example. On Bet365, the odds for Gregoire Barrere to win are 1.80, and the odds for Thanasi Kokkinakis to win are 2.00. We know that even a big name like Bet365 has a profit margin, so let’s see what the “true odds” are with our fair odds calculator.

Barrere to Win: 

No-Vig % /True Probability: 52.63%

No Vig Odds / True Odds: 1.90

Kokkinakis to Win: 

No-Vig % /True Probability: 47.37%

No Vig Odds / True Odds: 2.11

We can now quickly compare those odds between other sportsbooks. On Unibet, the odds are 1.81 for Barrere to win and 1.96 for Kokkinakis to win. When you compare those “true” odds to Bet365, we can glean that it would be better to bet on Barrere to win on Unibet and best to go on Bet365 to bet on Kokkinakis since those two options give us the closest odds to the “true” odds.

Why Should You Calculate Fair Odds When Betting?

Fair odds is one of the most easy-to-understand popular betting strategies. By choosing the sportsbook or odds that offer you the closest to the true probability or fair odds, you give less money to the house and get more money back. It’s a simple, sensible step that can be used for two-way results. The best part is that this calculator can also be used alongside other betting strategies.

This is because fair odds are used primarily to help you find the most competitive odds. If you bet on multiple sportsbooks, you can quickly understand which operator is the best one for that game. The vig, juice, or house edge changes game by game, with operators working with a higher or lower house edge depending on the bet type and popularity.

Does Fair Odds Betting Work On All Sports?

Our fair odds betting calculator can be used in most sports, though not at all times. Here are some ideal situations:

Two-Outcome Events

Tennis is a great example since there cannot be a draw as a match outcome. You can also use this calculator for non-sports-related options. For example, betting on who the next president is going to be. Any two-outcome game or event is a good fit for this calculator without any other strategies needed.

Multi-Event Exceptions

You can also use this two-outcome calculator if the match you want to bet on is in a tournament, playoff, or final. A football (soccer) final, for example, will go into overtime, then sudden death if it’s a tie, so one must come out as the winner. You can also use the half or quarter Asian handicap method to virtually remove the chance of a draw (in terms of your bet, not actual outcomes) and then use this calculator.

Is this a bit limiting? Yes, but we offer many other calculators, like our Parlay Fair Odds calculator, an odds converter, an accumulator calculator and beyond! So, if this calculator doesn’t suit your style, try one of our others.

Get Started with Our Fair Odds Calculator

Our fair odds calculator is entirely free to use and can be used without limits whenever betting on two-way events to find the true probability and no-vig odds in seconds.

All you have to do is enter the two outcomes of your event and press ‘Calculate’ to get instant results. When using the inputs, remember that this is a fair odds calculator in decimal; it won’t work with American or fractional odds.

Fair Odds calculator


Three Benefits To Using a Fair Odds Calculator

Using any calculator means that more steps will be involved in your betting strategy, but we have three key reasons why the extra effort is worth it. All calculators can be instrumental to expanding your betting calculator, yes, but when it comes to two-way events, our calculator stands out for these top reasons:

Benefit 1: Gives You Clear Insight Into the House Edge

Knowing the fair odds of a game means seeing right through the house edge, making it a snap to find the best sportsbooks that give you the most competitive odds. Since you can easily see the odds written out, you can compare them directly to other top-rated betting sites rather than doing the maths for each website.

Benefit 2: Saves You Time By Doing Multiple Calculations at Once

Calculating the true probability and the no-vig odds takes multiple calculations. Unless you’re a whizz at mental arithmetic, going through all those steps will take time. Our calculator does all that in the background, saving you time and effort.

Benefit 3: Gives You Two Outputs to Improve Your Betting Strategy

Our calculator gives you both the true probability and the true odds, meaning you can better understand how the sportsbook expects the game to play out. It also means that you can quickly find the best odds for your chosen bet when you cross-compare between sportsbooks.

Introducing the Best Bookmakers for Fair Odds Betting

The best sportsbooks already give you some of the lowest vig around, making your efforts to bet with the fairest odds already far easier. However, this doesn’t mean it’s not worth checking to see which of the top dogs offers you the best odds for the game. It just makes cross-comparing sportsbooks that much faster. To help you start out with the best of the best, offering some of the most competitive odds, check out some of the best bookies:

Tips for Using Our Fair Odds Calculator

Our calculator handles all those pesky formulas for you, but it can only do so much. You still need to use the calculator correctly to get accurate, usable results. To help you do just that, we’ve put together a few key tips that you’ll want to keep in mind when using our calculator.

Make Sure the Event Only Has Two Outcomes

Our fair odds calculating tool only works with two-option events, so sports where there’s a winner or a loser, with no draw. If this doesn’t suit the type of event you want to bet on, however, don’t worry. We have other available calculators for three or more outcome events (like horse racing or games where there’s a win/lose or a draw option) that you can use instead.

Input the Odds Correctly

This is such a simple mistake, but if you get the odds format or odds themselves wrong when you input them, you won’t get accurate results, so double check that the odds format and odds you put in are true to what you see on your go-to sportsbook. Our calculator currently accepts decimal format.

Be Ready to Continue Your Investigation

Some calculators can tell you if your bet is worthwhile. This fair odds one does not, it just tells you what the true probability and no-vig odds are. You then need to go and compare those true odds with other sportsbooks and bonuses, so you know the best place to place your bet.

Our Other Great Sports Betting Calculators to Try Out

We have over 15 different sports betting calculators for you to choose from making it an absolute cinch to find the calculator that suits your preferred sports betting strategy. Whatever your fancy, find your calculator here:

Start Using Our Fair Odds Calculator Today

Our fair odds calculator helps you easily pick out the true odds and probability in a flash so that you can make smarter decisions about where you place your bet. Just remember to double-check that the odds are correct and that you’re using it with two-way events only to get the most accurate results. Since this calculator can be used alongside other sports strategies and calculators, think of it as a useful reconnaissance step that suits all types of bettors.

Boost Your Fair Odds Strategy with These Top Bonuses

Online betting bonuses can be useful no matter your bet style. They are often low-risk ways to beef up your betting strategy and experience with a boosted bankroll, and they come in many forms, depending on the bonus you choose.

For the fair odds approach, for example, stick with an odds boost, which can help you increase the available odds on the wager you want to make closer to the true odds (or even better). Not sure which sportsbook to go to for those great bonuses? Check out our top five bookies:

Fair Odds Betting Calculator FAQs

🆚 What’s the difference between implied probability and true probability?

True probability is the probability of an event happening based on the available odds, with the house edge taken out of the equation. Implied probability is the probability of an event happening with the house edge included.

🧃What’s the difference between vig and juice?

Both terms are simply slang for the house edge or profit margin. When you calculate the vig, it should reflect a percentage over 100%. Whatever that difference is, it’s how much the bookie collects on that bet.

💲 What’s a competitive house edge?

You should only bet on sportsbooks that regularly have a house edge or vig under 10%. The closer the house edge to 0%, the more competitive the odds are because it means the bookie is taking less of a profit margin. Top providers like Bet365, for example, regularly have a house edge between 4 to 6%.

🤔 Does the house edge stay the same?

No, the house edge will change from game to game. That’s why you’ll want to use our fair odds calculator before every match, even if you’re using the same sportsbook.

📲 How do I include an odds bonus boost in my calculations?

You’ll first want to apply the bonus to a potential bet (but don’t make it yet!). Then, use the odds on your bet slip into our fair odds calculator to determine the true probability and odds for comparison.