How to read prediction market odds
Turn a price in cents into decimal, fractional or American odds and an implied chance, with a table.
The price is the implied chance
On a prediction market a price of 40¢ means the market gives the outcome about a 40% chance. You pay 40¢ and get $1 back if it happens.
Decimal odds
Decimal odds are 1 divided by the price in dollars. 40¢ is 1 / 0.40 = 2.50. A $100 stake returns $250, which is $150 profit. Sigorum shows decimal odds next to every pick.
American odds
Below 50¢ (an underdog), American odds are +(100 / price − 100): 40¢ is +150. Above 50¢ (a favourite), they are −(price × 100 / (1 − price)): 60¢ is −150.
Conversion table
| Price | Implied chance | Decimal | American |
|---|---|---|---|
| 20¢ | 20% | 5.00 | +400 |
| 30¢ | 30% | 3.33 | +233 |
| 40¢ | 40% | 2.50 | +150 |
| 50¢ | 50% | 2.00 | +100 |
| 60¢ | 60% | 1.67 | −150 |
| 70¢ | 70% | 1.43 | −233 |
| 80¢ | 80% | 1.25 | −400 |
Why price matters
Winning often is not enough. A pick at 80¢ has to win more than 4 times in 5 just to break even. That is why Sigorum tracks profit and return on stake, not only the share of picks that won. See the full record.