Guide
Decimal odds explained
Decimal odds are the standard across European football markets, and they are the format used throughout this site. They are the easiest format to calculate with because the number already includes your stake.
How to read them
A price of 2.50 means a €10 stake returns €25.00 in total: €15.00 profit plus your €10 back. Anything below 2.00 is an odds-on selection; anything above 2.00 is odds-against.
total_return = stake × decimal_odds profit = stake × (decimal_odds − 1)
Converting between formats
The three common formats describe the same thing in different units.
- Fractional to decimal: 5/2 → (5 ÷ 2) + 1 = 3.50
- Decimal to fractional: 3.50 → 3.50 − 1 = 2.5 → 5/2
- Decimal to American: above 2.00 → (odds − 1) × 100; below 2.00 → −100 ÷ (odds − 1)
Why decimals suit staking maths
Every staking formula on this site — flat, percentage, Kelly, recovery — takes decimal odds directly. Kelly in particular uses b = decimal_odds − 1, so no conversion step is needed and no rounding error creeps in.