Definition
A favorite is the side priced as more likely to win. In American odds, the favorite is shown with a minus sign, such as -150 or -220. The number tells you how much you must risk to win $100 in profit.
For negative American odds, implied probability is:
odds / (odds + 100)
using the positive value of the minus price. A -150 favorite has an implied probability of:
150 / (150 + 100) = 0.60, or 60%.
Worked Example
A team is listed at -110 on the moneyline. A $110 bet wins $100 in profit, plus the $110 stake back, for a total return of $210.
The implied probability is:
110 / (110 + 100) = 0.5238, or 52.38%.
If the same team moves to -150, the payout becomes smaller relative to the risk. A $150 bet wins $100 in profit, and the implied probability rises to 60%.
Why It Matters
Knowing the favorite price helps a bettor compare the market’s expectation against their own projection. A favorite is only worth betting when the price is better than the bettor’s estimated win probability.