Definition
American Odds (Moneyline Odds)
Also known as Moneyline Odds, US Odds, American Format
By Abhinav VasudevanReviewed Editorial policy
In short
American odds use a baseline of 100. A positive number is the profit on a $100 stake (+250 wins $250). A negative number is the stake needed to win $100 (-150 means risking $150 to win $100).
American odds are the standard format in US sportsbooks. They are built around a $100 reference point, and the sign tells you which side of even money you are on.
The two halves
Positive odds (+). The underdog. The number is the profit on a $100 stake.
- +250 → stake $100, win $250, receive $350
- +120 → stake $100, win $120, receive $220
Negative odds (−). The favourite. The number is the stake required to win $100.
- −150 → stake $150 to win $100, receive $250
- −400 → stake $400 to win $100, receive $500
You do not have to stake $100; the odds simply scale. A $25 bet at +250 wins $62.50.
The gap around even money
There is no zero. The scale runs from −100 to +100 with nothing in between, because both represent even money. Stake $100 to win $100. Books write this as +100 or occasionally EVEN.
Prices just either side, like −105 and +105, are very close together despite the sign flip. This is the one genuinely counterintuitive feature of the format.
Converting
To decimal:
- Positive: (odds ÷ 100) + 1 → +250 becomes 3.50
- Negative: (100 ÷ |odds|) + 1 → −150 becomes 1.67
- Positive: 100 ÷ (odds + 100) → +250 gives 28.6%
- Negative: |odds| ÷ (|odds| + 100) → −150 gives 60.0%
| American | Decimal | Implied |
|---|---|---|
| +400 | 5.00 | 20.0% |
| +200 | 3.00 | 33.3% |
| +100 | 2.00 | 50.0% |
| −110 | 1.91 | 52.4% |
| −200 | 3.00 → 1.50 | 66.7% |
| −500 | 1.20 | 83.3% |
Why -110 is everywhere
Standard point spread and totals markets are priced −110 on both sides. That is the vigorish. Risk $110 to win $100 on a proposition designed to be close to a coin flip.
It means you need to win 52.38% of your bets to break even. Books offering −105 reduce that to about 51.2%, which over a season is frequently the whole difference between profit and loss.
Common questions
What does +250 mean?
You win $250 profit on a $100 stake, returning $350 in total. The plus sign marks the underdog. You do not have to stake $100, since the odds scale: a $25 bet at +250 wins $62.50.
What does -150 mean?
You must risk $150 to win $100, returning $250 in total. The minus sign marks the favourite. The bigger the number after the minus, the shorter the price and the more you must risk for the same return.
Why is there no zero in American odds?
Because the scale runs from -100 to +100 with nothing between, and both represent even money. Prices either side of the gap, like -105 and +105, are much closer together than the sign flip suggests.