How to convert American odds
American odds show how much profit you can win relative to a $100 stake or risk. Positive odds show profit on a $100 winning bet. Negative odds show how much you need to risk to win $100.
| Odds | Meaning | Implied probability |
|---|---|---|
| +150 | Risk $100 to win $150 | 40.00% |
| -120 | Risk $120 to win $100 | 54.55% |
| +250 | Risk $100 to win $250 | 28.57% |
| -200 | Risk $200 to win $100 | 66.67% |
Formula for American odds to probability
For positive odds, divide 100 by the odds plus 100. For negative odds, divide the absolute value of the odds by the absolute value plus 100. This gives the break-even probability before vig.
Use odds conversion with EV, not in isolation
Odds conversion tells you the sportsbook's implied break-even number. It does not tell you whether the bet has value. To estimate expected value, compare the implied probability to your own true probability estimate, then use the EV calculator or the best EV betting tools guide.
Related calculators and betting research tools
If you need broader conversions, use the betting odds converter. To size a bet after you find value, use the Kelly Criterion calculator or the bankroll management calculator. To research a real bet slip on your phone, compare tools in the sports betting research app guide.
Responsible betting: These calculators are educational tools, not financial advice or guaranteed picks. Only bet what you can afford to lose. If gambling is causing harm, call 1-800-522-4700 in the U.S.