Free Odds Converter
Convert Betting Odds Instantly - All Formats
American Odds
Decimal Odds
Fractional Odds
Implied Probability
Understanding Betting Odds Formats
The odds converter is an essential tool for any sports bettor. Different regions and sportsbooks use different odds formats, and being able to quickly convert between them helps you compare lines, find the best value, and understand the true probability of outcomes. Our free betting odds converter instantly translates between American, Decimal, and Fractional odds while calculating the implied probability in real-time.
American Odds (Moneyline)
Used primarily in the United States, American odds show how much you need to bet to win $100 (negative odds) or how much you win on a $100 bet (positive odds).
- Negative odds (-150): Bet $150 to win $100
- Positive odds (+200): Bet $100 to win $200
- Even money is represented as +100
Decimal Odds (European)
Popular in Europe, Canada, and Australia, decimal odds show your total return per unit staked, including your original bet.
- Calculation: Stake × Decimal Odds = Total Return
- 2.50 odds: $10 bet returns $25 total
- Always greater than 1.00
Fractional Odds (UK)
Traditional in the UK and Ireland, fractional odds show potential profit relative to your stake.
- Format: Profit/Stake (e.g., 5/2)
- 5/2 odds: Win $5 for every $2 staked
- "Odds-on" when denominator is larger (1/2)
Odds Conversion Quick Reference Table
| American | Decimal | Fractional | Implied Probability | $100 Bet Returns |
|---|---|---|---|---|
| -500 | 1.20 | 1/5 | 83.33% | $120 |
| -200 | 1.50 | 1/2 | 66.67% | $150 |
| -150 | 1.67 | 2/3 | 60.00% | $167 |
| -110 | 1.91 | 10/11 | 52.38% | $191 |
| +100 | 2.00 | 1/1 | 50.00% | $200 |
| +150 | 2.50 | 3/2 | 40.00% | $250 |
| +200 | 3.00 | 2/1 | 33.33% | $300 |
| +300 | 4.00 | 3/1 | 25.00% | $400 |
| +500 | 6.00 | 5/1 | 16.67% | $600 |
| +1000 | 11.00 | 10/1 | 9.09% | $1,100 |
How to Use the Odds Converter
Step 1: Choose Your Input Format
Click on any of the three input fields - American, Decimal, or Fractional. The converter automatically detects which field you're using.
Step 2: Enter Your Odds
- American: Include the + or - sign (e.g., +150 or -200)
- Decimal: Enter as a decimal number greater than 1 (e.g., 2.50)
- Fractional: Use forward slash format (e.g., 5/2 or 3/1)
Step 3: View All Conversions
The other formats update automatically in real-time, along with the implied probability percentage and potential payouts for different bet amounts.
Ready to Use These Odds?
After converting your odds, compare them across the best betting sites to ensure you're getting the best value on your wagers.
Implied Probability Explained
Implied probability is the conversion of betting odds into a percentage that shows the likelihood of an outcome according to the bookmaker. It's crucial for identifying value bets - when your assessment of an outcome's probability is higher than the bookmaker's implied probability, you've found potential value.
Implied Probability Formulas:
- From Decimal Odds: (1 ÷ Decimal Odds) × 100
- From American Odds (Positive): 100 ÷ (American Odds + 100) × 100
- From American Odds (Negative): (-American Odds) ÷ (-American Odds + 100) × 100
- From Fractional Odds: Denominator ÷ (Numerator + Denominator) × 100
Betting Fraction Calculator
Our odds converter doubles as a fraction calculator for betting. Convert any fractional odds like 5/2, 7/4, or 11/8 to decimal and American formats instantly. Understanding fractions is crucial for horse racing, UK betting, and traditional sportsbooks.
Common Betting Fractions Quick Reference
Odds-On Favorites
- 1/2 (Bet $2 to win $1)
- 1/3 (Bet $3 to win $1)
- 2/5 (Bet $5 to win $2)
- 4/7 (Bet $7 to win $4)
Even Money & Slight Odds
- 1/1 (Even money)
- 6/4 (Bet $4 to win $6)
- 7/4 (Bet $4 to win $7)
- 2/1 (Bet $1 to win $2)
Long Shots
- 10/1 (Bet $1 to win $10)
- 20/1 (Bet $1 to win $20)
- 50/1 (Bet $1 to win $50)
- 100/1 (Bet $1 to win $100)
Odds Converter for Different Sports
NFL Betting Odds Converter
NFL bettors primarily use American odds. Common conversions include:
- -110 (standard point spread)
- -200 to -300 (heavy favorites)
- +150 to +500 (underdogs)
Our converter helps compare odds across different sportsbooks quickly.
Soccer Betting Odds Converter
Soccer uses decimal odds in Europe and fractional in the UK. Converting between 1X2 markets, Asian handicaps, and US sportsbooks requires quick conversion.
Example: Decimal odds of 2.50 equals +150 American or 3/2 fractional.
Horse Racing Odds Converter
Traditional fractional odds like 5/2, 7/1, and 15/2 need conversion for modern betting apps. Our tool instantly converts morning line odds to decimal or American formats.
Tip: Use decimal odds for easier payout calculations.
Advanced Odds Conversion Formulas
Hong Kong Odds Conversion
Hong Kong odds show profit only (similar to fractional numerator). To convert:
- HK to Decimal: HK odds + 1
- Decimal to HK: Decimal odds - 1
- Example: HK 0.5 = 1.50 decimal = -200 American
Indonesian Odds Conversion
Indonesian odds are similar to American but divided by 100:
- Positive Indo odds = American odds ÷ 100
- Negative Indo odds = -100 ÷ American odds
Malay Odds Conversion
Malaysian odds can be positive or negative with different meanings than American:
- Positive Malay = Decimal odds - 1
- Negative Malay = 1 ÷ (1 - Malay odds) for decimal
Why Convert Betting Odds?
Compare Different Sportsbooks
Many sportsbooks use different default formats. Converting allows you to quickly compare sportsbooks and find the best value across multiple betting sites.
Even small differences in odds compound over time.
Understand True Value
Implied probability helps you identify when odds offer value. If you believe a team has a 60% chance to win but the odds imply only 50%, that's a potential value bet.
Always compare implied probability to your own assessment.
Calculate Payouts Easily
Decimal odds make payout calculations simple - just multiply your stake by the decimal odds. Converting to decimal can simplify your betting math significantly.
Quick mental math becomes much easier.
Frequently Asked Questions
How do you convert American odds to decimal?
To convert American odds to decimal: For positive odds (+150), divide by 100 and add 1. So +150 = (150/100) + 1 = 2.50. For negative odds (-200), divide 100 by the absolute value and add 1. So -200 = (100/200) + 1 = 1.50.
What is implied probability in betting?
Implied probability shows the likelihood of an outcome based on the betting odds. It's calculated by dividing 1 by the decimal odds and multiplying by 100. For example, decimal odds of 2.00 = (1/2.00) × 100 = 50% implied probability.
Which odds format is best for betting?
Decimal odds are often considered the easiest to understand and calculate. They show your total return per unit staked. However, American odds are standard in the US, while fractional odds are traditional in the UK. Our converter lets you work with whatever format you prefer.
How do fractional odds work?
Fractional odds show potential profit relative to stake. Odds of 5/2 mean you win $5 for every $2 staked, plus your stake back. To convert to decimal, divide the first number by the second and add 1. So 5/2 = (5÷2) + 1 = 3.50 decimal odds.
What does -110 mean in betting?
-110 is the standard American odds for point spreads and totals. It means you need to bet $110 to win $100. This represents a 52.38% implied probability and includes the sportsbook's vigorish (vig). In decimal format, -110 equals 1.91.
How do I know if odds offer good value?
Compare the implied probability to your own assessment. If odds of +200 (33.33% implied probability) are offered on an outcome you believe has a 40% chance of occurring, that's a value bet. Always look for odds where the implied probability is lower than your estimated true probability.
Published by: Robert Wood, Topend Sports, July 2025
Last Updated:
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