Odds Conversion Calculator
Convert between decimal, fractional and American odds formats.
About Odds Conversion Calculator
All three formats express the same information. Decimal odds include the stake in the return, which is why the implied probability is simply the reciprocal. The implied probability is also the break-even win rate, which is the number that determines whether a bet has value.
Formula
Odds Conversion
Implied probability = 1 ÷ decimal odds; American odds derive from the same figure
- decimal odds
- Total return per unit staked, including the stake
- implied probability
- The probability the odds correspond to
Worked example
With the default values below, Odds Conversion Calculator returns Implied Probability of 28.5714%. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Decimal oddsaccepts 1.01–1,000
- 3.5
Results
- Implied Probability
- 28.5714%
- Fractional Odds
- 5/2
- American Odds
- 250
- Net Profit per Unit Staked
- 2.5000
- Break-Even Win Rate
- 28.5714%
Step by step
- 1Values used
- 2Odds Conversion
- 3Implied Probability= 28.5714
- 4Fractional Odds= 5/2
- 5American Odds= 250
- 6Net Profit per Unit Staked= 2.5000
- 7Break-Even Win Rate= 28.5714
Assumptions and limits
- The result is derived only from the single input listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
- These figures are estimates based on population-average formulas and are intended for training and recreational planning only. They are not medical advice. Consult a qualified health professional before starting or changing an exercise programme, particularly if you have an existing medical condition.
- This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
These figures are estimates based on population-average formulas and are intended for training and recreational planning only. They are not medical advice. Consult a qualified health professional before starting or changing an exercise programme, particularly if you have an existing medical condition.
Frequently Asked Questions
How is Odds Conversion calculated?
Implied probability = 1 ÷ decimal odds; American odds derive from the same figure All three formats express the same information. Decimal odds include the stake in the return, which is why the implied probability is simply the reciprocal.
Why does Odds Conversion matter?
The implied probability is also the break-even win rate, which is the number that determines whether a bet has value.
What values do I need to enter?
This calculator takes 1 input: Decimal odds. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.