Betting Calculators – Odds, Probabilities, and Bookmakers’ Margins
In sports betting, the odds shown by a bookmaker don’t directly reflect the real probability of an event happening. On top of the potential payout, they also bake in the bookmaker’s margin – the commission that guarantees their profit over the long run.
That’s precisely why the real odds and real probabilities differ from what you see at the bookmaker. Understanding this difference is the foundation of successful odds analysis, spotting Value Bets and building a winning sports betting strategy. Using the calculators below, you can easily work out the real odds, probabilities and the bookmaker’s margin in just a few seconds.
Calculator for Actual Odds, Probabilities, and Margin
Want to find out what a bookmaker’s margin is? Enter the odds and the calculator will work out not just the margin, but also the real probability and the real odds you’d expect at zero margin.
What does this calculator do?
When a bookmaker sets the odds for a given market, they build in their own margin (commission), which reduces the real value of those odds. This calculator strips out the margin and shows what the real (fair) odds and real probabilities would be if the bookmaker’s edge didn’t exist.
It’ll also work out the bookmaker’s margin for you, letting you easily compare different bookmakers and judge where you’re getting better value for your bets.
How do you interpret the results?
Enter the odds for the two or three possible outcomes of the event, and the calculator will automatically work out the real probabilities, the real odds and the margin percentage. The lower the margin, the closer the odds on offer are to the real probability of the event happening.
Low margins generally mean better betting conditions, since less of the potential payout gets swallowed up by the bookmaker.
Practical Example
Say a bookmaker offers odds of 1.80 for the home side, 3.20 for the draw and 4.20 for the away side in a Premier League match. Once you enter these into the calculator, you’ll see exactly what margin is baked in and what the real odds would be without it. This makes it easy to compare offers across different bookmakers and pick the one with the most favourable terms, which matters a great deal when betting over the long term.
Margin is the best way to objectively compare odds between different bookmakers. The average margin at one of the most popular bookmakers, bet365, sits at around 6%, while at Pinnacle it’s typically between 2% and 3%. A lower margin means better odds and a higher potential return over the long run. If you want to compare more bookmakers, check out this full comparison of bookmakers by margin.
Calculator for Converting Odds to Probability
Find out what chance the bookmaker’s odds imply for an event happening, using our mathematical predictions. If you believe the real chance is higher and you’ve got the information to back that up, you could be looking at positive value.
What does this calculator show?
Every odd offered by a bookmaker corresponds to a specific implied probability for that event happening. With this calculator, you can instantly find out what chance the bookmaker is giving a particular outcome, without doing the maths by hand.
This is one of the most useful tools for analysing sports bets, since it helps you judge whether the odds on offer match up with your own assessment of the probability.
When is it useful?
This calculator is especially useful once you’ve already analysed a match and want to compare your own assessment against what the odds imply. If you reckon the real probability of the event happening is higher than what the calculator works out, you may well have spotted a value bet.
Practical Example
A bookmaker offers odds of 2.50 for a team to win in La Liga. Once you enter this into the calculator, you’ll get an implied probability of 40%. If, after doing your own analysis, you reckon the real chance of that win is closer to 50%, that means you believe the bookmaker has undervalued the probability, and the bet could offer positive value. This is exactly how professional analysts use probabilities when assessing odds.
Probability-to-Odds Converter
Find out what odds correspond to the probability you believe an event has of happening. If the odds implied by your own probability are lower than the ones offered by the bookmaker, you could be looking at positive value.
What does this calculator show?
While the previous calculator converts odds into a probability, this one works the other way around. Enter the probability you believe reflects the real chance of an event happening, and the calculator will automatically work out the real (fair) odds that match that assessment.
This is a handy tool for anyone building their own match prediction and wanting to know the minimum odds they should accept for the bet to have value.
When to use it?
After analysing a match, you’ll often have your own estimate of the probability for the different outcomes. Instead of relying solely on the bookmaker’s odds, you can enter your own probability into the calculator and get the fair odds in return. Then simply compare it with what the bookmaker’s offering – if their odds are higher, you may well have found a value bet.
Practical Example
After a detailed analysis of a match of Champions League, you reckon a given team has a 60% chance of winning. Enter that figure into the calculator and you’ll get a real odds of 1.67. If the bookmaker’s offering 1.85, that’s higher than the fair odds based on your assessment, and it could represent a value bet. If they’re offering 1.55, though, there’s no potential value there, and it’s probably not worth placing the bet.
How to find a Value Bet using our betting calculators?
Spotting value bets isn’t just about finding a high price – it’s about working out whether that price is higher than the real probability of the event happening. That’s exactly why the three calculators on this page work best when used together.
Step 1: Check the odds
Start with the odds the bookmaker’s offering on your chosen bet. This shows how the market is rating the chances of that event happening.
Step 2: Convert it to a probability
Use the odds-to-probability calculator to find out what probability that price implies. This will show you the bookmaker’s assessment, expressed as a percentage.
Step 3: Compare it with your own evaluation
After doing your own analysis of the match, work out what you believe the real probability of the event happening is. If you reckon it’s higher than the figure the calculator worked out, there’s good reason to keep digging.
Step 4: Check whether the bet has value
Enter your own probability into the probability-to-odds calculator and see what the real (fair) odds work out to. If the bookmaker’s offering higher odds than the calculator’s fair price, you may well have found a Value Bet – a bet with positive expected value over the long run.
No calculator can predict the outcome of a match, but it can help you make more informed decisions. Combined with in-depth analysis, stats and good betting discipline, these tools are a valuable aid for anyone looking to assess odds like a professional.
Table of Odds and Probabilities
| 1.01 = 99.01% | 1.31 = 76.34% | 1.61 = 62.11% | 1.91 = 52.36% | 4.10 = 24.39% |
| 1.02 = 98.04% | 1.32 = 75.76% | 1.62 = 61.73% | 1.92 = 52.08% | 4.20 = 23.81% |
| 1.03 = 97.09% | 1.33 = 75.19% | 1.63 = 61.35% | 1.93 = 51.81% | 4.30 = 23.26% |
| 1.04 = 96.15% | 1.34 = 74.63% | 1.64 = 60.98% | 1.94 = 51.55% | 4.40 = 22.73% |
| 1.05 = 95.24% | 1.35 = 74.07% | 1.65 = 60.61% | 1.95 = 51.28% | 4.50 = 22.22% |
| 1.06 = 94.34% | 1.36 = 73.53% | 1.66 = 60.24% | 1.96 = 51.02% | 4.60 = 21.74% |
| 1.07 = 93.46% | 1.37 = 72.99% | 1.67 = 59.88% | 1.97 = 50.76% | 4.70 = 21.28% |
| 1.08 = 92.59% | 1.38 = 72.46% | 1.68 = 59.52% | 1.98 = 50.51% | 4.80 = 20.83% |
| 1.09 = 91.74% | 1.39 = 71.94% | 1.69 = 59.17% | 1.99 = 50.25% | 4.90 = 20.41% |
| 1.10 = 90.91% | 1.40 = 71.43% | 1.70 = 58.82% | 2.00 = 50.00% | 5.00 = 20.00% |
| 1.11 = 90.09% | 1.41 = 70.92% | 1.71 = 58.48% | 2.10 = 47.62% | 6.00 = 16.67% |
| 1.12 = 89.29% | 1.42 = 70.42% | 1.72 = 58.14% | 2.20 = 45.45% | 7.00 = 14.29% |
| 1.13 = 88.50% | 1.43 = 69.93% | 1.73 = 57.80% | 2.30 = 43.48% | 8.00 = 12.50% |
| 1.14 = 87.72% | 1.44 = 69.44% | 1.74 = 57.47% | 2.40 = 41.67% | 10.00 = 10.00% |
| 1.15 = 86.96% | 1.45 = 68.97% | 1.75 = 57.14% | 2.50 = 40.00% | 15.00 = 6.67% |
| 1.16 = 86.21% | 1.46 = 68.49% | 1.76 = 56.82% | 2.60 = 38.46% | 20.00 = 5.00% |
| 1.17 = 85.47% | 1.47 = 68.03% | 1.77 = 56.50% | 2.70 = 37.04% | 50.00 = 2.00% |
| 1.18 = 84.75% | 1.48 = 67.57% | 1.78 = 56.18% | 2.80 = 35.71% | 100.00 = 1.00% |
| 1.19 = 84.03% | 1.49 = 67.11% | 1.79 = 55.87% | 2.90 = 34.48% | 200.00 = 0.50% |
| 1.20 = 83.33% | 1.50 = 66.67% | 1.80 = 55.56% | 3.00 = 33.33% | 300.00 = 0.33% |
| 1.21 = 82.64% | 1.51 = 66.23% | 1.81 = 55.25% | 3.10 = 32.26% | 400.00 = 0.25% |
| 1.22 = 81.97% | 1.52 = 65.79% | 1.82 = 54.95% | 3.20 = 31.25% | 500.00 = 0.20% |
| 1.23 = 81.30% | 1.53 = 65.36% | 1.83 = 54.64% | 3.30 = 30.30% | 600.00 = 0.17% |
| 1.24 = 80.65% | 1.54 = 64.94% | 1.84 = 54.35% | 3.40 = 29.41% | 700.00 = 0.14% |
| 1.25 = 80.00% | 1.55 = 64.52% | 1.85 = 54.05% | 3.50 = 28.57% | 800.00 = 0.13% |
| 1.26 = 79.37% | 1.56 = 64.10% | 1.86 = 53.76% | 3.60 = 27.78% | 900.00 = 0.11% |
| 1.27 = 78.74% | 1.57 = 63.69% | 1.87 = 53.48% | 3.70 = 27.03% | 1000.00 = 0.10% |
| 1.28 = 78.13% | 1.58 = 63.29% | 1.88 = 53.19% | 3.80 = 26.32% | 2000.00 = 0.05% |
| 1.29 = 77.52% | 1.59 = 62.89% | 1.89 = 52.91% | 3.90 = 25.64% | 5000.00 = 0.02% |
| 1.30 = 76.92% | 1.60 = 62.50% | 1.90 = 52.63% | 4.00 = 25.00% | 10000.00 = 0.01% |
You don’t always need to use a calculator to work out what probability a given price implies. If you’re after a quick reference, our odds-to-probability table shows the most common odds and their corresponding implied probability.
It’s especially handy when you want to quickly compare different odds without plugging values into a calculator. For more precise calculations, real (fair) odds, or working out the bookmaker’s margin, use the calculators above.
Use the odds working in your favor
Now that you know how to work out real odds, probabilities and bookmaker margins, you’ve got the core tools for making more informed sports betting decisions. Combine these calculations with in-depth match analysis, and spotting bets with potential value becomes a lot easier.
If you’d rather save yourself the analysis time, check out our professional football predictions, whether you’re following the Bundesliga, Serie A or any of the other top leagues – where we publish thoroughly reasoned selections every day, built on stats, form, team news and the search for Value Bets. That way, you can put the principles covered on this page into practice.