Betting calculators remove guesswork and ensure you always know exactly what your potential return, risk, and edge are before placing a bet.
1. Odds Converter
Converts between the three main odds formats instantly:
| Decimal | Fractional | American |
|---|---|---|
| 2.00 | 1/1 (evens) | +100 |
| 3.00 | 2/1 | +200 |
| 1.50 | 1/2 | -200 |
| 4.00 | 3/1 | +300 |
Essential when comparing odds across bookmakers that use different formats, or when reading tipsters who quote in fractional while your bookmaker uses decimal.
2. Accumulator Calculator
Enter the odds for each leg of your accumulator and your stake. The calculator shows:
- Total potential return including stake
- Profit (return minus stake)
- Each-way returns if applicable
- Rule 4 deductions for withdrawn runners
A £5 four-fold at odds of 2.00, 3.00, 1.50, and 4.00 returns £5 × 2.00 × 3.00 × 1.50 × 4.00 = £180 (profit: £175).
3. Dutching Calculator
Splits your total stake across multiple selections so you win the same amount regardless of which selection wins. Enter the odds for each selection and your total budget.
4. Matched Betting Calculator
Calculates the lay stake needed on an exchange to match a bookmaker's back bet for matched betting. Enter the back odds, lay odds, exchange commission, and bet type (qualifying or free bet) to see the optimal lay stake and guaranteed profit.
5. Margin Calculator
Reveals the bookmaker's built-in edge by converting odds to implied probabilities:
Example: A football 1X2 market with odds of 2.50, 3.40, 2.80:
- Home: 1/2.50 = 40.0%
- Draw: 1/3.40 = 29.4%
- Away: 1/2.80 = 35.7%
- Total: 105.1% — the bookmaker's margin is 5.1%
Markets with margins below 5% offer better value. Betting exchanges consistently offer the lowest margins.
6. Kelly Criterion Calculator
Calculates your optimal stake size based on your estimated edge and available odds. Enter your estimated probability and the bookmaker's odds to determine what percentage of your bankroll to wager.
7. Arbitrage Calculator
Identifies whether an arbitrage opportunity exists across multiple bookmakers and calculates the stakes needed to guarantee profit.