Quick Answer
Betting odds show two things: how much you can win and the implied probability of an outcome. American odds use + and - symbols, decimal odds show total return per $1 bet, and fractional odds show profit relative to stake.
The Three Odds Formats
Sportsbooks around the world use different odds formats. American odds are standard in the US, decimal odds dominate in Europe and Australia, and fractional odds are traditional in the UK. All three formats represent the same information in different ways.
American Odds (Moneyline)
American odds are displayed with a plus (+) or minus (-) sign. This is the most common format at US sportsbooks.
Understanding + and - Odds
Shows how much you WIN on a $100 bet
+150 means you win $150 profit on a $100 bet
Shows how much you must BET to win $100
-150 means you must bet $150 to win $100 profit
American Odds Examples
Decimal Odds
Decimal odds are the simplest format. The number shows your total return for every $1 wagered, including your original stake.
Total Payout = Stake x Decimal Odds
Decimal odds of 2.00 represent even money (same as +100 American or 1/1 fractional). Any decimal below 2.00 means you are betting on a favorite. Above 2.00 means you are betting on an underdog.
Fractional Odds
Fractional odds (like 5/2 or 3/1) show your profit relative to your stake. The first number is your potential profit, the second is how much you bet.
Profit = Stake x (Numerator / Denominator)
Odds Conversion Chart
Use this chart to quickly convert between odds formats:
| American | Decimal | Fractional | Implied Probability |
|---|---|---|---|
| +500 | 6.00 | 5/1 | 16.67% |
| +200 | 3.00 | 2/1 | 33.33% |
| +150 | 2.50 | 3/2 | 40.00% |
| +100 | 2.00 | 1/1 | 50.00% |
| -110 | 1.91 | 10/11 | 52.38% |
| -150 | 1.67 | 2/3 | 60.00% |
| -200 | 1.50 | 1/2 | 66.67% |
| -500 | 1.20 | 1/5 | 83.33% |
Understanding Implied Probability
Implied probability tells you the chance of an outcome occurring according to the odds. It is essential for finding value bets.
Implied Probability Formulas
Probability = 100 / (Odds + 100)
Example: +200 = 100/(200+100) = 33.33%
Probability = |Odds| / (|Odds| + 100)
Example: -150 = 150/(150+100) = 60%
Probability = 1 / Decimal Odds
Example: 2.50 = 1/2.50 = 40%
What is the Vig (Juice)?
The vig (or juice) is the sportsbook's built-in commission. It is why odds on both sides of a bet do not add up to 100% implied probability.
Example: Standard Point Spread
On a typical point spread, both sides are -110:
- Team A -3 (-110) = 52.38% implied probability
- Team B +3 (-110) = 52.38% implied probability
- Total: 104.76% (The extra 4.76% is the vig)
Calculating Your Payout
Here are the formulas to calculate potential payouts:
American Odds Payout
Profit = Stake x (Odds / 100)
$50 at +200 = $50 x (200/100) = $100 profit
Profit = Stake x (100 / |Odds|)
$150 at -150 = $150 x (100/150) = $100 profit
Pro Tips for Reading Odds
- ✓Compare odds across multiple sportsbooks to find the best value
- ✓Look for sportsbooks with lower vig (reduced juice lines)
- ✓Use our odds converter tool to quickly switch between formats
- ✓Calculate implied probability to assess if odds offer value
Key Takeaways
- ✓American odds: + shows profit on $100 bet, - shows amount to bet to win $100
- ✓Decimal odds: Multiply by stake for total return (including stake)
- ✓Fractional odds: First number is profit, second is stake required
- ✓Implied probability reveals the true value in odds
- ✓The vig is why total implied probabilities exceed 100%