Odds Converter
Convert between decimal, fractional, and American odds — and see the implied probability — in one place. Edit any field and the others update live. Handy when you're comparing prices across our reviewed operators or browsing casinos & sportsbooks. 18+.
2 decimal = 1/1 = +100 American = 50% implied probability.
How it works
Decimal odds are the canonical form: implied probability = 1 ÷ decimal. American odds derive from decimal (≥2.0 → positive, <2.0 → negative), and fractional is the reduced fraction of (decimal − 1).
Worked example
Decimal 2.50 = fractional 3/2 = American +150 = implied probability 40%. If you think the true chance is higher than 40%, the price has value.
Odds converter FAQ
How do I convert decimal odds to implied probability?
Implied probability = 1 ÷ decimal odds. Decimal 2.00 = 1/2 = 50%. Decimal 1.50 = 66.7%.
How do decimal and American odds relate?
For decimal ≥ 2.0, American = (decimal − 1) × 100. For decimal < 2.0, American = −100 ÷ (decimal − 1). Decimal 2.50 = +150; decimal 1.50 = −200.
What is the 'vig' and does this show it?
Bookmakers price implied probabilities that sum to more than 100% — the overround or vig. This tool converts a single price; compare both sides' implied probabilities to see the margin.