Odds, Probability & Bankroll
American odds
American odds are a moneyline odds format used by US bookmakers that shows either the profit on a $100 stake (positive odds) or the stake required to win $100 (negative odds).
Key points
- The odds format is a moneyline quotation that encodes payout rather than direct probability24.
- A positive quote means the bet is on an underdog; a negative quote means the bet is on a favourite1.
- The odds apply at the time the bet is placed and the payout on that wager is fixed1.
- American odds are commonly used in US sportsbooks for straight-up moneyline wagers with no point spread12.
How to read American odds
| Odds | Stake | Profit if win | Total return |
|---|---|---|---|
| +200 | $100 | $200 | $300 |
| -150 | $150 | $100 | $250 |
| +100 | $100 | $100 | $200 |
Common questions
How do american odds work?
American odds use a plus or minus sign. Positive odds (e.g., +200) show the profit on a $100 bet. Negative odds (e.g., -150) show the stake needed to win $100 profit.1
How to read american odds?
If the odds are positive, the number is your profit on a $100 stake. If negative, the number is the amount you must bet to win $100. The total return includes your original stake.1
How to convert american odds to decimal?
For positive odds: (odds/100) + 1. For negative odds: (100/|odds|) + 1. For example, +200 becomes 3.00, and -150 becomes 1.67.3
Where this term is used
Related terms
Sources
- Fixed-odds betting en.wikipedia.org Defines American odds and explains the plus/minus system.
- Odds en.wikipedia.org Provides context on odds as a ratio and the moneyline format.
- Sports betting en.wikipedia.org Gives the even money value and conversion formulas.
- Relative vs absolute risk and odds: Understanding the difference pmc.ncbi.nlm.nih.gov Supports the distinction between betting odds and probability ratios.
Sources are drawn from regulators, universities and published research, and each one is labelled with what it actually is — a preprint is not called a paper. Bookmaker and affiliate pages are never cited here, because a page that sells betting is not a neutral authority on it.