Odds Converter
Convert between American, Decimal, and Fractional odds formats instantly
Less work, more wins
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Common Odds Reference
Quick reference table for the most common betting odds across all formats
| American | Decimal | Fractional | Implied Probability |
|---|---|---|---|
| -200 | 1.50 | 1/2 | 66.67% |
| -150 | 1.67 | 2/3 | 60.00% |
| -110 | 1.91 | 10/11 | 52.38% |
| +100 | 2.00 | 1/1 | 50.00% |
| +110 | 2.10 | 11/10 | 47.62% |
| +120 | 2.20 | 6/5 | 45.45% |
| +130 | 2.30 | 13/10 | 43.48% |
| +140 | 2.40 | 7/5 | 41.67% |
| +150 | 2.50 | 3/2 | 40.00% |
| +160 | 2.60 | 8/5 | 38.46% |
| +170 | 2.70 | 17/10 | 37.04% |
| +180 | 2.80 | 9/5 | 35.71% |
| +200 | 3.00 | 2/1 | 33.33% |
| +250 | 3.50 | 5/2 | 28.57% |
| +300 | 4.00 | 3/1 | 25.00% |
| +400 | 5.00 | 4/1 | 20.00% |
| +500 | 6.00 | 5/1 | 16.67% |
| +750 | 8.50 | 15/2 | 11.76% |
| +1000 | 11.00 | 10/1 | 9.09% |
| +2000 | 21.00 | 20/1 | 4.76% |
How to Use the Odds Converter
Enter odds in any format and instantly see the equivalent in all other formats. Our converter handles American (+/-), Decimal, and Fractional odds.
Choose a Format
Click on American, Decimal, or Fractional to select your input format
Enter Your Odds
Type in the odds you want to convert. The calculator accepts any valid odds value
View Conversions
Instantly see the equivalent odds in all three formats plus implied probability
Understanding Betting Odds Formats
Every sportsbook displays odds differently, and confusion costs you money. An odds converter eliminates the guesswork by instantly translating between American, decimal, and fractional formats so you can compare prices and find the best value.
American odds use plus and minus signs (+150, -120), decimal odds show your total return (2.50, 1.83), and fractional odds display profit as a ratio (3/2, 5/6). These are three ways to express the same probability, but each format tells you something different at a glance. US sportsbooks prefer American odds, European books use decimals, and UK bookmakers stick with fractions. If you're shopping for the best line across multiple books, you need to speak all three languages fluently.
The math behind odds conversion is straightforward but easy to mess up manually. Decimal to American requires different formulas depending on whether it's a favorite or underdog. Fractional to decimal needs precise division. Our converter handles all the calculations instantly and also shows implied probability — the percentage chance the bookmaker thinks an outcome will happen. When implied probability across all outcomes exceeds 100%, that's the bookmaker's edge. The lower the total, the better value you're getting.
Implied probability is where odds conversion becomes powerful for bettors. If you think an outcome has a 60% chance of happening but the odds imply only 50%, that's a value bet. Most bettors focus on picking winners, but professional bettors focus on finding odds that don't match true probability. The converter calculates this instantly so you can spot when a bookmaker has mispriced a line. It's the difference between betting randomly and betting with an edge.
Beyond basic conversion, serious bettors need tools that track odds movement across dozens of bookmakers in real-time. BetSmarter's premium platform monitors line changes, alerts you to steam moves (when odds shift rapidly due to sharp money), and highlights value opportunities before they disappear. Stop manually checking odds — let technology do the heavy lifting while you focus on finding profitable spots.
Frequently Asked Questions
American odds use positive numbers for underdogs and negative numbers for favorites. +200 means you win $200 on a $100 bet. -150 means you must bet $150 to win $100. The larger the negative number, the bigger the favorite. The larger the positive number, the bigger the underdog. American odds are standard at US sportsbooks like DraftKings, FanDuel, and BetMGM.
Convert decimal odds to probability by dividing 1 by the odds (1 ÷ 2.50 = 40%). For American odds: if negative, divide the odds by odds plus 100 (-150: 150/(150+100) = 60%). If positive, divide 100 by odds plus 100 (+200: 100/(200+100) = 33.3%). For fractional odds (3/1), divide denominator by numerator plus denominator (1/(3+1) = 25%). The converter does this math instantly for all formats.
Regional preference and tradition. American odds originated in the US and emphasize favorites vs underdogs through positive and negative numbers. Decimal odds became standard in Europe because they're simpler for math—they show your total return multiplier. Fractional odds have been used in UK betting for centuries and clearly show profit as a ratio. All three formats express the same probability, just in different mathematical notation. Modern sportsbooks often let you choose your preferred display format.