Positive odds
Positive odds are one of two types of odds used in American odds. Positive odds represent the underdog in a bet, meaning this outcome is considered less likely to happen than not.
Positive odds indicate how much money would be won from a $100 bet.
For example, if odds of +300 were quoted, then a $100 bet would see returns of $300 and a total payout of $400.
Odds of +100 are also referred to as evens, meaning the bookmaker is suggesting that the chance of the outcome occurring is 50/50.
The opposite of positive odds are negative odds, which represent the favourite in a bet, meaning this outcome is considered more likely to happen than not.
Calculating returns with positive odds
It is relatively straight forward to calculate returns using positive odds if you are placing a $100 bet - but often this is not the exact figure of our stake. To calculate returns on a positive odds bet, the following formula is used:
Stake * (odds / 100)
For example
Arsenal vs Chelsea - Arsenal to win odds of +250 with a $10 bet stake
10 * (250 / 100) = 25
Therefore returns would be $25.
Converting positive odds into decimal odds
The formula for converting positive odds into decimal odds is as follows:
Odds / 100 + 1
For example
Atalanta vs Roma - over 2.5 goals at odds of +150
150 / 100 + 1 = 2.50
Converting positive odds into fractional odds
In order to convert American odds into fractional odds, the odds are arranged in a certain way and then reduced to their simplest form. To convert positive odds into fractional odds, the odds are arranged as follows:
Odds/100
And then reduced into simplest form.
For example
Barcelona vs Real Madrid - Real Madrid to win at odds of +300
300/100 reduces down into 3/1
Converting positive odds into implied probability
Implied probability is the conversion of odds into a percentage to show the expected probability of an outcome.
The formula for converting positive odds into implied probability is as follows:
100 / (odds + 100) * 100 = implied probability
For example
Chelsea to beat Manchester United at odds of +200
100 / (200 + 100) * 100 = 33.3%