Glossary
Odds
Betting odds are the price of a bet. They set how much a winning bet pays and, read closely, they reveal how likely the sportsbook thinks an outcome is. Odds come in three formats: American, decimal, and fractional, each expressing the same thing in a different style.
Odds do two jobs at once. They tell you the payout on a winning bet, and they encode a probability. A price of -200 pays less than +150 because the -200 side is judged more likely to win.
The three common formats say the same thing differently. American odds are built around 100, using minus for favorites and plus for underdogs. Decimal odds show the total return per unit staked, including the stake. Fractional odds show profit as a fraction of the stake.
Learning to convert a price into an implied probability is what turns odds from a payout table into a decision tool. Once you can do that, you can ask the only question that matters: is this price fair for the risk.
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