Betting Odds Explained: Decimal Odds, Probability & Markets
Odds are a price, not a prediction guarantee. In decimal format, the number represents the total return per unit staked if the bet wins, including the original stake.
How decimal odds work
At decimal odds of 2.50, a stake of 100 would return 250 if the bet wins: 100 × 2.50. The profit component would be 150 because the return includes the original 100 stake.
Implied probability
A simple implied probability estimate is 1 ÷ decimal odds. Odds of 2.50 imply 40%; odds of 1.80 imply about 55.6%. This is a price-derived figure, not a guarantee of the true chance.
Why odds move
Prices can move because of new information, market activity, model updates or live-event changes. In-play prices can move especially fast.
Settlement still depends on the market rule
Even when you understand the odds, the bet still settles according to the operator's definition of the selected market. Read the market label and settlement terms.
Worked odds examples
Use two calculations separately: potential return = stake × decimal odds; implied probability = 1 ÷ decimal odds. They answer different questions—one about payout if successful, the other about the probability embedded in the quoted price.
| Decimal odds | Stake | Potential total return | Implied probability |
|---|---|---|---|
| 2.00 | 100 | 200 | 50.0% |
| 2.50 | 100 | 250 | 40.0% |
| 1.80 | 100 | 180 | 55.6% |
| 3.20 | 100 | 320 | 31.25% |