American Odds – How do they work?
12 July 2019
If you live in the UK or Europe then you will most likely be familiar with either decimal odds, fractional odds or both. They’re the two most common odds formats and you’ll find them available on any bookmaker site you come across.
However, when changing the odds at a bookmaker or betting on sports in the USA, you may have noticed a number of other odds formats with one being ‘American Odds’.
So, what are American Odds and how do they work?
American odds work differently to decimal and fractional odds and you may never use them. However, they aren’t too complicated to understand and they may come in handy one day so it’s worth understanding how they work.
American odds start with either a ‘+’ or a ‘-‘. For example ‘+145’ or ‘-145’.
- If the odds are negative (-), this means that you must bet this amount in order to make £100 profit.
- If the odds are positive (+), this is the amount of profit you will make if you bet £100 and your bet wins.
Let’s take a look at some examples.
Two NFL teams are playing and you bet on ‘Team A’ who have odds of -145.
As the odds are negative, we know that if we bet £100 and our bet wins, we will make £145 profit.
‘Team B’ have odds of +145
As the odds are positive, we know that we will make £145 profit if we bet £100 and our bet wins.
Pretty simple, yes?
Well, they are simple if you are using £100 stakes or aim to make a profit of £100. However, all of our bets aren’t going to be for these amounts so how do we calculate our returns with varying stakes?
Thankfully, we can use a simple formula for this depending on whether the odds are positive or negative.
Positive American Odds Formula
- Potential Profit = Odds x (stake/100)
Example: We bet £15 at odds of +145
145 x (15/100) = Potential Profit = 21.75
Negative American Odds Formula
- Potential Profit = (100/Odds) x stake
Example: We bet £17 at odds of -145
(100/145) x 17 = Potential Profit = 11.72
Conclusion
We can see that American Odds work differently to fractional and decimal odds which also work differently to each other. However, they are relatively simple to understand and when using certain stakes, are actually easier to calculate your returns. Whether you’ll use American odds in the future or not, they are useful to understand.
| Fraction | Decimal | American | Implied Probability |
|---|---|---|---|
| 1/5 | 1.20 | -500 | 83.3% |
| 2/9 | 1.22 | -450 | 81.8% |
| 1/4 | 1.25 | -400 | 80% |
| 2/7 | 1.29 | -350 | 77.8% |
| 3/10 | 1.30 | -333.3 | 76.9% |
| 1/3 | 1.33 | -300 | 75% |
| 4/11 | 1.36 | -275 | 73.3% |
| 4/9 | 1.44 | -225 | 69.2% |
| 1/3 | 1.33 | -300 | 75% |
| 5/4 | 2.25 | 125 | 44.4% |
| 11/8 | 2.38 | 137.5 | 42.1% |
| 9/1 | 10.00 | 900 | 10% |
| 10/1 | 11.00 | 1000 | 9.1% |
| 20/1 | 21.00 | 2000 | 4.8% |
| 50/1 | 51.00 | 5000 | 2% |
| 100/1 | 101.00 | 10000 | 1% |
| 1000/1 | 1001.00 | 100000 | 0.1% |