The same price is written three ways. In Europe you will nearly always see decimal odds, in Britain fractional, in the US American. It is one number in different clothes.
The three formats
| Decimal | Fractional | American | Probability |
|---|---|---|---|
| 1.50 | 1/2 | −200 | 66.7% |
| 2.00 | 1/1 | +100 | 50% |
| 3.00 | 2/1 | +200 | 33.3% |
| 5.00 | 4/1 | +400 | 20% |
Decimal is the easiest for calculation. Multiply the stake by the odds and you see the total you get back. Every lesson here uses decimal odds.
The core markets
| Market | What you predict | Wins when |
|---|---|---|
| 1X2 | The result after 90 minutes | Your chosen outcome happens |
| Double chance | 1X, X2 or 12 | One of two outcomes happens |
| Over/Under 2.5 | Total goals | Over: 3 goals or more. Under: 2 or fewer |
| BTTSi | Both teams score | Both score at least once |
| Draw no bet | 1 or 2 without the draw | Stake returned on a draw |
| Corners and cards | Total corners or cards | Over/under on a line, e.g. 9.5 corners |
Half lines (2.5, 9.5) have no refund: the bet wins or loses. Whole-number lines (2, 3) refund the stake when the result lands exactly on them.
Example
A match with Over 2.5 at 1.85. Stake 10 and 3 or more goals are scored: you get back 18.50 (profit 8.50). With 2 goals you lose the 10.
The market you choose changes the margin you pay. Next, how we measure whether a price is worth it: expected value.