Odds Converter
Enter any odds in any format and instantly see American, Decimal, Fractional, and implied probability — all at once. Essential when switching between US and international sportsbooks.
Odds Converter
Quick examples
Odds Format Guide
American Odds (Moneyline)
-110 or +150
Used in the United States. A negative number shows how much you must bet to win $100. A positive number shows how much you win from a $100 bet. -110 means bet $110 to win $100. +150 means bet $100 to win $150.
Decimal Odds (European)
1.91 or 2.50
Standard in Europe, Australia, and Canada. Multiply your stake by the decimal to get your total return including your original stake. 2.50 on a $100 bet returns $250 total — $150 profit plus your $100 back.
Fractional Odds (UK)
10/11 or 3/2
The traditional UK and Irish format, common in horse racing. The left number is your profit, the right is your stake. 3/2 means win $3 for every $2 bet. Evens (1/1) means you win the same amount as your stake.
Implied Probability
52.4% or 40%
The break-even win rate implied by the odds — the percentage of the time you need to win to make a profit at those odds. If your true win rate exceeds the implied probability, you have a positive expected value edge.
Quick Reference Conversion Table
| American | Decimal | Fractional | Implied % |
|---|---|---|---|
| -200 | 1.50 | 1/2 | 66.7% |
| -150 | 1.67 | 2/3 | 60.0% |
| -110 | 1.91 | 10/11 | 52.4% |
| +100 | 2.00 | 1/1 (Evens) | 50.0% |
| +110 | 2.10 | 11/10 | 47.6% |
| +150 | 2.50 | 3/2 | 40.0% |
| +200 | 3.00 | 2/1 | 33.3% |
| +300 | 4.00 | 3/1 | 25.0% |
| +500 | 6.00 | 5/1 | 16.7% |
How to Convert Odds Manually
American to Decimal
If positive: Decimal = (American / 100) + 1 → +150 becomes (150/100) + 1 = 2.50
If negative: Decimal = (100 / |American|) + 1 → -200 becomes (100/200) + 1 = 1.50
Decimal to Implied Probability
Implied % = (1 / Decimal) × 100 → 2.50 becomes (1/2.50) × 100 = 40%
Fractional to Decimal
Decimal = (numerator / denominator) + 1 → 3/1 becomes (3/1) + 1 = 4.00
The converter above handles all of these instantly — the manual formulas are useful to understand the math behind what the tool calculates.
Understanding the Vig (House Edge)
When you add up the implied probabilities of both sides of any market, the total will always exceed 100%. That excess is the bookmaker's margin — commonly called the "vig", "juice", or "overround".
A standard NFL point spread is priced at -110 on both sides. Each side implies 52.4% probability. Together: 104.8%. The extra 4.8% is the book's built-in profit.
A lower vig means better value for the bettor. Comparing vig across sportsbooks — especially for the same market — is one of the most effective ways to improve long-term returns. Our odds converter makes this comparison instant.
Frequently Asked Questions
Which odds format should I use?
Use whichever format your sportsbook displays. The converter exists precisely so you do not need to pick one — enter what you see and view all formats simultaneously. Most US bettors default to American; most European bettors default to Decimal.
What does "implied probability" actually mean?
Implied probability is the win rate that the odds suggest you need to break even over the long run. If a team is priced at +200 (implied 33.3%), you need to win at least 33.4% of the time at those odds to be profitable. Anything above that is expected value.
How do I know if the odds are good value?
Compare the implied probability to your own estimate of the true probability. If you think a team has a 50% chance of winning but the odds imply 40%, those odds offer positive expected value (+EV). The EV Calculator can help you quantify this.
Why do different sportsbooks show different odds for the same game?
Each sportsbook sets its own lines based on its own models, bet intake, and risk management strategy. Differences between books create the price gaps that bettors exploit through line shopping and arbitrage betting.