Tool · Calculator
Odds converter
Convert between American, decimal, and fractional odds and the implied probability they represent. Type any format and see the rest instantly — the fastest way to compare a sportsbook line against a prediction-market price (which is already an implied probability).
american
+150
decimal
2.50
fractional
3/2
Implied prob.
40.0%
How the math works
- American → decimal: +150 = 1 + 150/100 = 2.50; −200 = 1 + 100/200 = 1.50.
- Decimal → implied probability: 1 / decimal. 2.50 → 40%.
- Fractional → decimal: 3/2 = 1.5 + 1 = 2.50.
- Why it matters: a prediction-market YES price is an implied probability (62¢ = 62%). Convert a sportsbook line to a probability to see which venue prices the same outcome better.
See live prices across platforms on the Odds Desk.