152→ Odds
From odds to probability
Type the odds and see the probability behind them. With two or three outcomes the calculator also shows the bookmaker margin and the fair odds.
Odds of 2.10 say it happens about 48 times in 100.
$1,000 × 2.10 = $2,100payout, of which $1,100 is profit
Bookmaker margin 5.7%
The chances add up to 105.7%, not 100%. The extra is the margin the bookmaker keeps.
| Outcome | With margin | Fair chance | Fair odds |
|---|---|---|---|
| Home 2.10 | 47.6% | 45.1% | 2.22 |
| Draw 3.30 | 30.3% | 28.7% | 3.49 |
| Away 3.60 | 27.8% | 26.3% | 3.81 |
Fair chance = (1 ÷ odds) ÷ sum of all (1 ÷ odds). This is the proportional method.
The maths in one line
Probability = 1 ÷ odds
Example: 1 ÷ 2.50 = 40%: odds of 2.50 pay as if it happened 40% of the time.
How to read odds
- PayoutDecimal odds already include your stake: $1,000 × 2.50 = $2,500.
- ProfitYour profit is the payout minus the stake: $1,500.
- ProbabilityOne divided by the odds is the probability that price pays for, not the real probability.
A sample 1X2 market
| Item | Value |
|---|---|
| Odds | 2.10 · 3.30 · 3.60 |
| Sum of probabilities | 105.7% |
| Bookmaker margin | 5.7% |
| Home, with margin | 47.6% |
| Home, no margin | 45.1% |
| Fair odds for home | 2.22 |
Computed with the proportional method.
More odds maths
Questions
What is implied probability?
It is one divided by the odds. It shows how often something would have to happen for that price to be even, before the margin.
Why do the probabilities of a match add up to more than the whole?
Because the bookmaker adds a margin to every price. In the example above the three probabilities add up to 105.7%.
What are fair odds?
Odds without the margin: one divided by the fair probability. They help you compare prices, not guess results.