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Odds Converter

Convert between American, Decimal, Fractional, and Implied Probability in real time. Edit any format, the others update.

10/11
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Quick Reference

AmericanDecimalFractionalImplied

About the Odds Converter

Different sportsbooks and regions use different odds formats. American odds (-110, +150) are standard in the U.S., Decimal odds (1.91, 2.50) dominate Europe and Australia, Fractional odds (10/11, 3/2) are still used in the UK, and Implied Probability is the format pro bettors think in.

Use this converter when you need to translate odds across formats — for example, comparing a U.S. moneyline to a European Pinnacle price, or working out the implied probability of a +180 underdog at a glance.

Frequently asked questions

How do I convert American odds to implied probability?
For positive odds: 100 / (odds + 100). For negative odds: |odds| / (|odds| + 100). So +150 implies 40%, and -200 implies 66.7%.
What's the easiest way to compare lines across books?
Convert every price to implied probability or decimal odds. Both are linear and easy to compare side-by-side. American odds are nonlinear (the gap between +100 and +200 is much larger than between -100 and -200), which makes mental math harder.
What's the difference between decimal odds and the multiplier?
Decimal odds include your stake. A $100 bet at 2.50 returns $250 total ($150 profit + $100 stake). Multiplier (or 'to 1') odds exclude the stake — 3/2 means you win $150 in profit on a $100 bet.
Can I convert odds without using a calculator?
For mental math, memorize a few anchor points: -110 ≈ 52.4%, +100 = 50%, +150 = 40%, +200 = 33.3%, -200 = 66.7%. Most other lines fall close enough to one of these to estimate.

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