Betting Tools

What is a True Odds Calculator?

A true odds calculator is an essential tool for any serious bettor. It works by removing the bookmaker's margin (also known as "vigorish" or "juice") from the odds, revealing the real probability of an outcome. Every bookmaker builds a margin into their odds to guarantee themselves a profit, regardless of the event's result. This means the odds you see don't reflect the true statistical probability.

By understanding the true odds, you can more accurately assess the value of a bet and make smarter, more profitable decisions in the long run.

How to Use This Calculator

1. Select the number of possible outcomes for the event (e.g., 2 for a tennis match, 3 for a football match including a draw).
2. Choose the odds format you're using (Decimal, Fractional, or American).
3. Enter the odds for each outcome into the corresponding input boxes.
4. The calculator will instantly update, showing you the bookmaker's margin and a table with the "true odds" and "true probability" for each outcome.

Interpreting the Results

The "Derived True Odds" table shows you the odds without the bookmaker's profit margin. By comparing these true odds to the odds offered, you can identify "value bets"—a core concept you can explore further with our Expected Value Calculator.

What is a Reverse Odds Calculator?

A reverse odds calculator is a simple but powerful tool that flips the standard odds calculation on its head. Instead of converting odds into a probability, it converts your own estimated probability into the "true odds" you should be looking for from a bookmaker.

How to Use This Calculator

1. Research an event and form your own opinion on the likelihood of an outcome.
2. Enter your estimated win probability as a percentage (e.g., "55" for 55%).
3. The calculator will instantly show you the "Required True Odds" for that probability.

Interpreting the Results

The result is the minimum decimal odd you should accept from a bookmaker to consider a bet as having value. If the bookmaker's odds are higher than the "Required True Odds" displayed, you have likely found a value bet.

What is an Odds Converter?

An odds converter is a utility that translates betting odds between the three major formats: Decimal (e.g., 2.50), Fractional (e.g., 6/4), and American (e.g., +150). It also calculates the implied probability for those odds. This is crucial for bettors who use international bookmakers or want to quickly understand the likelihood of an outcome.

How to Use This Calculator

1. Enter the odds you want to convert into the input box.
2. Select the format you are converting *from* using the dropdown menu.
3. The calculator will instantly display the equivalent odds in all three formats, plus the implied probability percentage.

What is an Expected Value (EV) Calculator?

Expected Value (EV) is one of the most important concepts in sports betting. It tells you how much you can expect to win or lose on average if you were to place the same bet an infinite number of times. A positive EV (+EV) indicates a profitable long-term bet, while a negative EV (-EV) suggests it's a losing bet over time. Professional bettors exclusively hunt for +EV opportunities.

How to Use This Calculator

1. Enter your stake in your chosen currency.
2. Enter the decimal odds offered by the bookmaker.
3. Use the toggle to choose your estimation method: either your own assessed Win Probability (%) or the True Odds you believe are correct.
4. The calculator will instantly show your Expected Value for that bet.

Interpreting the Results

The result shows your average profit or loss per bet. For example, an EV of +£0.50 on a £10 stake means that, on average, you would expect to make a profit of 50p every time you place that bet. If the result is green and positive, you've likely found a value bet. These principles are the foundation of our betting strategy, which you can see in our proven results.

What is an Arbitrage Calculator?

An arbitrage bet (or "arb") is a risk-free betting opportunity that arises from discrepancies in the odds offered by different bookmakers. By betting on all possible outcomes of an event across different bookies, you can guarantee a profit regardless of the result. Our arbitrage calculator identifies these opportunities and tells you exactly how much to stake on each outcome.

How to Use This Calculator

1. Enter the total amount you wish to stake across all bets.
2. Enter the highest decimal odds you can find for each outcome of the event (e.g., Outcome 1 from Bookmaker A, Outcome 2 from Bookmaker B).
3. Use the "+ Add Outcome" button if there are more than two possible results.
4. The calculator will instantly tell you if an arbitrage opportunity exists.

Interpreting the Results

If the result is green and says "Arbitrage Found!", it will show your guaranteed profit percentage and the exact stake to place on each outcome to lock in that profit. If it shows "No Arbitrage Opportunity," the combined margin is too high for a risk-free bet.

What is the Kelly Criterion?

The Kelly Criterion is a mathematical formula used for bankroll management. It calculates the optimal size of a bet to maximize long-term growth. It's a powerful tool for serious bettors because it prevents you from staking too much on one bet while ensuring you capitalize effectively when you identify a value opportunity (+EV bet), which you can find using our Expected Value Calculator.

How to Use This Calculator

1. Enter your total betting bankroll.
2. Enter the decimal odds for the bet you are considering.
3. Enter your estimated win probability for that bet (you can use the true probability from our other tools).
4. The calculator will tell you the exact amount and percentage of your bankroll to stake.

Interpreting the Results

The result is the mathematically optimal amount to bet to grow your bankroll safely. If it shows "No Value Detected," it means the Kelly Criterion advises against placing the bet because your estimated probability is not high enough to overcome the bookmaker's odds.