Implied probability chart: decimal, American and fractional odds
The implied probability of odds from 1.10 to 10.00 in decimal, American and fractional form, the formulas and how often picks at these prices really win.
For every pick, BetBuddyRank turns the odds into a probability and compares it with the final score: 27,082 priced tipster picks from X so far, winning 51.4% of the time against 51.9% expected. Below is the chart for odds from 1.10 to 10.00, the formulas for all three formats and data on how well odds describe what actually happens.
The probabilities in the chart are raw, without removing the vig: 1 divided by the decimal odds. American odds are rounded to whole numbers and fractional odds are shown in their usual form.
| Decimal | American | Fractional | Implied probability |
|---|---|---|---|
| 1.10 | −1000 | 1/10 | 90.9% |
| 1.20 | −500 | 1/5 | 83.3% |
| 1.25 | −400 | 1/4 | 80.0% |
| 1.30 | −333 | 3/10 | 76.9% |
| 1.40 | −250 | 2/5 | 71.4% |
| 1.50 | −200 | 1/2 | 66.7% |
| 1.60 | −167 | 3/5 | 62.5% |
| 1.70 | −143 | 7/10 | 58.8% |
| 1.80 | −125 | 4/5 | 55.6% |
| 1.90 | −111 | 9/10 | 52.6% |
| 1.91 | −110 | 10/11 | 52.4% |
| 2.00 | +100 | 1/1 | 50.0% |
| 2.10 | +110 | 11/10 | 47.6% |
| 2.20 | +120 | 6/5 | 45.5% |
| 2.40 | +140 | 7/5 | 41.7% |
| 2.50 | +150 | 3/2 | 40.0% |
| 2.75 | +175 | 7/4 | 36.4% |
| 3.00 | +200 | 2/1 | 33.3% |
| 3.50 | +250 | 5/2 | 28.6% |
| 4.00 | +300 | 3/1 | 25.0% |
| 4.50 | +350 | 7/2 | 22.2% |
| 5.00 | +400 | 4/1 | 20.0% |
| 6.00 | +500 | 5/1 | 16.7% |
| 7.00 | +600 | 6/1 | 14.3% |
| 8.00 | +700 | 7/1 | 12.5% |
| 9.00 | +800 | 8/1 | 11.1% |
| 10.00 | +900 | 9/1 | 10.0% |
Decimal odds
Odds of 1.80 give 1 / 1.80 = 55.6%.
American odds
Odds of −150 give 150 / 250 = 60%, odds of +250 give 100 / 350 = 28.6%.
Fractional odds
Odds of 5/2 give 2 / 7 = 28.6%, odds of 4/6 give 6 / 10 = 60%.
To go back: decimal odds = 1 / p. A 60% chance is 1.67 in decimal, −150 in American and 4/6 in fractional odds. Any format converts to any other with the odds converter.
Sportsbooks price a little below fair odds, so the implied probabilities of all outcomes of one market add up to more than 100%. To get the fair probability, divide each outcome’s implied probability by that sum.
| Outcome | Odds | Implied probability | No-vig probability |
|---|---|---|---|
| Home win | 2.10 (+110) | 47.6% | 45.4% |
| Draw | 3.40 (+240) | 29.4% | 28.1% |
| Away win | 3.60 (+260) | 27.8% | 26.5% |
| Total | - | 104.8% | 100% |
A total of 104.8% means a margin of 1 − 1 / 1.048, about 4.6%. A two-way market at −110 on both sides adds up to 104.8% as well, and the fair probability of each side is 50%. The no-vig calculator works out the margin and fair odds of any market.
Our tipster rating methodology takes the margin as 5%: the expected probability of a pick at odds k is 1 / (k × 1.05).
We split the priced singles of tipsters on X, up to odds of 30, into price bands and compared how often they win with the expectation from the odds minus the margin.
| Odds | Picks | Average odds | Expected | Hit rate | ROI |
|---|---|---|---|---|---|
| 1.01-1.49 | 3,711 | 1.37 | 69.9% | 69.5% | −5.3% |
| 1.50-1.89 | 11,901 | 1.72 | 55.6% | 56.1% | −3.6% |
| 1.90-2.29 | 7,033 | 2.02 | 47.3% | 48.0% | −3.3% |
| 2.30-3.49 | 2,070 | 2.61 | 36.9% | 37.4% | −3.2% |
| 3.50 and up | 408 | 5.80 | 20.0% | 24.3% | +50.8% |
Where there are thousands of picks, the hit rate stays close to the expectation: sportsbook odds describe the chances well, and the gap between 1 / odds and the real hit rate goes to the vig. That is why a hit rate a little above expectation is not yet a profit: check the ROI column. Above 3.50 there are few picks, and one long-odds winner moves ROI a lot.
- Break-even rate. Not to lose money at odds k, bets must win more often than 1 / k: above 52.4% at −110 (1.91), above 40% at +150 (2.50).
- Judging a pick. A pick has positive expected value when your estimate of the probability is above the implied one: p × k > 1 in decimal odds.
- Checking a tipster. Compare a tipster’s hit rate with the probability implied by their odds, not with 100%: 60% at odds near −200 (1.50) is a loss. More in the guide on how to check a tipster.
- Parlays. A parlay’s probability is the product of the leg probabilities: the math is in the guide on how parlays and system bets work.
What is the implied probability of +100 odds?
50% before the vig. Even money, +100 in American odds, is 2.00 in decimal and 1/1 in fractional odds. After a margin of about 5% the book rates the outcome at roughly 47.6%.
What odds equal a 60% chance?
Fair odds are −150 in American, 1.67 in decimal and 4/6 in fractional form. With a margin of about 5% a sportsbook would offer roughly −170 (1.59).
What does +200 mean in betting?
A $100 bet wins $200 in profit. That is 3.00 in decimal and 2/1 in fractional odds, an implied probability of 33.3%.
What does 5/2 mean in betting?
A stake of 2 wins 5 in profit. That is 3.50 in decimal and +250 in American odds, an implied probability of 28.6%.
How accurate are implied probabilities?
Quite accurate. In our data priced tipster singles at odds from 1.90 to 2.29 win 48.0% of the time against 47.3% expected, and all priced picks 51.4% against 51.9%.
- 1Find the odds of your pick in the chart and note the hit rate it takes to break even.
- 2Strip the margin out of a market with the no-vig odds calculator.
- 3Compare a tipster’s hit rate with their implied probability: find their profile with the tipster lookup by handle.