Odds Converter
Convert between American, Decimal, Fractional, and Implied Probability. Edit any field and the others update instantly.
What Each Format Means
American Odds
The default at PA sportsbooks. Negative numbers (e.g., -110) indicate favorites: bet that amount to win $100. Positive numbers (e.g., +110) indicate underdogs: bet $100 to win that amount.
Decimal Odds
European standard. Shows total return per $1 wagered (including stake). Example: 2.50 decimal = $2.50 total return per $1 = +150 American.
Fractional Odds
UK/Ireland tradition. Profit / stake. Example: 5/2 = win $5 profit for every $2 wagered (= $7 total return per $2 wagered = 3.50 decimal = +250 American).
Implied Probability
What the sportsbook estimates the chance of the outcome to be. Calculated from any odds format. -110 American implies 52.38% probability; +200 implies 33.33%.
Quick Reference
| American | Decimal | Fractional | Implied % |
|---|---|---|---|
| -200 | 1.500 | 1/2 | 66.67% |
| -150 | 1.667 | 2/3 | 60.00% |
| -110 | 1.909 | 10/11 | 52.38% |
| +100 | 2.000 | 1/1 (evens) | 50.00% |
| +150 | 2.500 | 3/2 | 40.00% |
| +200 | 3.000 | 2/1 | 33.33% |
| +500 | 6.000 | 5/1 | 16.67% |
| +1000 | 11.000 | 10/1 | 9.09% |
Formulas
- American → Decimal (favorite, negative): 100 / |American| + 1
- American → Decimal (underdog, positive): American / 100 + 1
- Decimal → Implied %: 1 / Decimal × 100
- Decimal → Fractional: Decimal − 1, expressed as fraction
- Implied % → Decimal: 100 / Implied %
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