Table of Contents
- Quick Answer {#quick-answer}
- American Odds Basics {#basics}
- Positive Odds Explained (+) {#positive}
- Negative Odds Explained (-) {#negative}
- Implied Probability {#probability}
- Odds Conversion Chart {#conversion}
- Calculating Payouts {#calculating}
- Common Mistakes {#mistakes}
- FAQ {#faq}
- Conclusion
- About the Author
- Disclaimer
Quick Answer {#quick-answer}
What does +200 mean?
+200 means you win $200 profit for every $100 you bet.
Bet: $100 at +200 odds
Profit: $200
Total Return: $300 ($200 profit + $100 stake)
What does -150 mean?
-150 means you need to bet $150 to win $100 profit.
Bet: $150 at -150 odds
Profit: $100
Total Return: $250 ($100 profit + $150 stake)
The Simple Rule:
- Positive (+) odds = Underdog (win more than you bet)
- Negative (-) odds = Favorite (bet more than you win)

American Odds Basics {#basics}
American odds (also called “moneyline odds”) are the standard format used by sportsbooks in the United States. They’re displayed as either positive or negative numbers.
Why Two Different Numbers?
American odds tell you two things at once:
- How much you’ll win (if positive)
- How much you need to bet (if negative)
This system originated from horse racing in the early 1900s and became standard for all US sports betting.
The $100 Standard
All American odds are based on a $100 benchmark:
| Odds Type | What $100 Represents |
|---|---|
| Positive (+) | $100 bet = X profit |
| Negative (-) | X bet = $100 profit |
This is why the math works differently for each.
Where You’ll See American Odds
- NFL betting: Every sportsbook
- NBA betting: Standard format
- MLB betting: Moneyline is primary bet type
- NHL betting: Puck line + moneyline
- College sports: All major sportsbooks
- International sports: Often shown alongside decimal odds
Positive Odds Explained (+) {#positive}
Positive odds represent underdogs — outcomes that are less likely to happen but pay more when they do.
How Positive Odds Work
Formula:
Profit = (Stake × Odds) ÷ 100
Example: +200 Odds
Stake: $100
Odds: +200
Profit: ($100 × 200) ÷ 100 = $200
Total Return: $300 ($200 profit + $100 stake)
Common Positive Odds
| Odds | $100 Bet Profit | Total Return | Implied Probability |
|---|---|---|---|
| +100 | $100 | $200 | 50.0% |
| +150 | $150 | $250 | 40.0% |
| +200 | $200 | $300 | 33.3% |
| +250 | $250 | $350 | 28.6% |
| +300 | $300 | $400 | 25.0% |
| +400 | $400 | $500 | 20.0% |
| +500 | $500 | $600 | 16.7% |
| +1000 | $1,000 | $1,100 | 9.1% |
Real-World Examples
Example 1: NFL Underdog
Denver Broncos +275 vs. Kansas City Chiefs
Bet $50 on Broncos → Win $137.50 if they win
Total return: $187.50
Example 2: NBA Moneyline
Miami Heat +180 vs. Boston Celtics
Bet $100 on Heat → Win $180 if they win
Total return: $280
Example 3: MLB Underdog
Oakland Athletics +220 vs. Houston Astros
Bet $25 on Athletics → Win $55 if they win
Total return: $80
When to Bet Positive Odds
✅ Good situations for underdog bets:
- You believe the underdog has a real chance to win
- The odds offer good value (higher than true probability)
- You’re making a small speculative bet
- In parlays for amplified payout
❌ Avoid when:
- The underdog is severely outmatched
- You’re betting large portions of your bankroll
- The odds don’t offer value (e.g., +105 on a 20% chance)
Negative Odds Explained (-) {#negative}
Negative odds represent favorites — outcomes that are more likely to happen but pay less.
How Negative Odds Work
Formula:
Profit = (Stake × 100) ÷ |Odds|
Example: -150 Odds
Stake: $150
Odds: -150
Profit: ($150 × 100) ÷ 150 = $100
Total Return: $250 ($100 profit + $150 stake)
Common Negative Odds
| Odds | Bet to Win $100 | Total Return | Implied Probability |
|---|---|---|---|
| -100 | $100 | $200 | 50.0% |
| -110 | $110 | $210 | 52.4% |
| -150 | $150 | $250 | 60.0% |
| -200 | $200 | $300 | 66.7% |
| -250 | $250 | $350 | 71.4% |
| -300 | $300 | $400 | 75.0% |
| -400 | $400 | $500 | 80.0% |
| -500 | $500 | $600 | 83.3% |
Real-World Examples
Example 1: NFL Favorite
Kansas City Chiefs -190 vs. Denver Broncos
Bet $190 on Chiefs → Win $100 if they win
Total return: $290
Example 2: NBA Heavy Favorite
Boston Celtics -350 vs. Miami Heat
Bet $350 on Celtics → Win $100 if they win
Total return: $450
Example 3: MLB Pitching Matchup
Houston Astros -165 vs. Oakland Athletics
Bet $50 on Astros → Win $30.30 if they win
Total return: $80.30
The -110 Standard
-110 is the most common odds you’ll see for point spreads and totals.
Why -110?
- Sportsbooks charge a “vig” or “juice” (their commission)
- Fair odds would be -105 on each side
- -110 gives the house a ~4.5% edge
Standard Spread Bet:
Patriots -3.5 (-110)
Jets +3.5 (-110)
Both sides have -110 odds
Sportsbook guarantees profit regardless of outcome
When to Bet Negative Odds
✅ Good situations for favorite bets:
- The favorite is significantly better
- You’re building a parlay foundation
- You want higher hit rate (more frequent wins)
- The odds still offer value
❌ Avoid when:
- The odds are too negative (-500 or worse)
- The risk/reward doesn’t make sense
- You’re chasing “safe” bets to recover losses
Implied Probability {#probability}
Implied probability tells you what chance the sportsbook thinks an outcome has based on the odds.
Calculating Implied Probability
For Positive Odds:
Implied Probability = 100 ÷ (Odds + 100) × 100
Example: +250
100 ÷ (250 + 100) × 100 = 28.6%
For Negative Odds:
Implied Probability = |Odds| ÷ (|Odds| + 100) × 100
Example: -200
200 ÷ (200 + 100) × 100 = 66.7%
Implied Probability Chart
| Odds | Implied Probability | Meaning |
|---|---|---|
| +500 | 16.7% | 1 in 6 chance |
| +300 | 25.0% | 1 in 4 chance |
| +200 | 33.3% | 1 in 3 chance |
| +150 | 40.0% | 2 in 5 chance |
| +100 | 50.0% | Coin flip |
| -100 | 50.0% | Coin flip |
| -150 | 60.0% | 3 in 5 chance |
| -200 | 66.7% | 2 in 3 chance |
| -300 | 75.0% | 3 in 4 chance |
| -500 | 83.3% | 5 in 6 chance |
Understanding Vig (Juice)
The sportsbook’s edge is built into the odds.
Example: Standard Spread
Patriots -3.5 (-110) → 52.4% implied probability
Jets +3.5 (-110) → 52.4% implied probability
Total: 104.8%
That extra 4.8% is the vig — the sportsbook’s guaranteed profit margin.
Removing the Vig (No-Vig Probability):
Patriots: 52.4% ÷ 104.8% = 50.0% true probability
Jets: 52.4% ÷ 104.8% = 50.0% true probability
Total: 100.0%
Finding Value Bets
Value exists when YOUR estimated probability > implied probability.
Example:
Team A: +200 (28.6% implied probability)
Your analysis suggests Team A has 40% chance to win.
Value Calculation:
(0.40 × $200) - (0.60 × $100) = $80 - $60 = +$20 EV
This is a +EV (positive expected value) bet!
Key Insight: Don’t just bet who you think will win. Bet when the odds offer better value than the true probability.

Odds Conversion Chart {#conversion}
Different regions use different odds formats. Here’s how to convert between them.
American ↔ Decimal Conversion
| American | Decimal | American | Decimal |
|---|---|---|---|
| +500 | 6.00 | -100 | 2.00 |
| +400 | 5.00 | -110 | 1.91 |
| +300 | 4.00 | -120 | 1.83 |
| +250 | 3.50 | -130 | 1.77 |
| +200 | 3.00 | -140 | 1.71 |
| +175 | 2.75 | -150 | 1.67 |
| +150 | 2.50 | -160 | 1.63 |
| +125 | 2.25 | -170 | 1.59 |
| +110 | 2.10 | -180 | 1.56 |
| +100 | 2.00 | -190 | 1.53 |
| -200 | 1.50 | ||
| -250 | 1.40 | ||
| -300 | 1.33 | ||
| -400 | 1.25 | ||
| -500 | 1.20 |
Conversion Formulas
American to Decimal:
Positive: (Odds ÷ 100) + 1
Example: +250 → (250 ÷ 100) + 1 = 3.50
Negative: (100 ÷ |Odds|) + 1
Example: -200 → (100 ÷ 200) + 1 = 1.50
Decimal to American:
Decimal ≥ 2.00: (Decimal - 1) × 100
Example: 3.50 → (3.50 - 1) × 100 = +250
Decimal < 2.00: -100 ÷ (Decimal - 1)
Example: 1.50 → -100 ÷ (1.50 - 1) = -200
American ↔ Fractional Conversion
| American | Fractional | American | Fractional |
|---|---|---|---|
| +500 | 5/1 | -100 | 1/1 |
| +400 | 4/1 | -110 | 10/11 |
| +300 | 3/1 | -120 | 5/6 |
| +250 | 5/2 | -130 | 10/13 |
| +200 | 2/1 | -150 | 2/3 |
| +150 | 3/2 | -200 | 1/2 |
| +125 | 5/4 | -250 | 2/5 |
| +110 | 11/10 | -300 | 1/3 |
| +100 | 1/1 | -400 | 1/4 |
Regional Format Preferences
| Region | Primary Format | Secondary |
|---|---|---|
| United States | American | Decimal |
| United Kingdom | Fractional | Decimal |
| Europe | Decimal | American |
| Canada | Decimal | American |
| Australia | Decimal | Fractional |
Calculating Payouts {#calculating}
Step-by-step payout calculations for any odds.
Quick Reference Formulas
For Positive Odds:
Profit = Stake × (Odds ÷ 100)
Total Return = Stake + Profit
For Negative Odds:
Profit = Stake × (100 ÷ |Odds|)
Total Return = Stake + Profit
Calculation Examples
Example 1: Positive Odds (+350)
Stake: $50
Odds: +350
Profit = $50 × (350 ÷ 100) = $50 × 3.5 = $175
Total Return = $50 + $175 = $225
Example 2: Negative Odds (-180)
Stake: $90
Odds: -180
Profit = $90 × (100 ÷ 180) = $90 × 0.556 = $50
Total Return = $90 + $50 = $140
Example 3: Different Stake Amounts
Odds: +250
$10 bet → $25 profit → $35 total
$25 bet → $62.50 profit → $87.50 total
$50 bet → $125 profit → $175 total
$100 bet → $250 profit → $350 total
$500 bet → $1,250 profit → $1,750 total
Parlay Calculations
For parlays, convert to decimal, multiply, then convert back.
Example: 3-Team Parlay
Leg 1: -110 → 1.91 decimal
Leg 2: +150 → 2.50 decimal
Leg 3: -130 → 1.77 decimal
Combined: 1.91 × 2.50 × 1.77 = 8.45 decimal
Convert to American: (8.45 - 1) × 100 = +745
$100 parlay bet → $745 profit → $845 total
Payout Table for Common Bets
| Odds | $10 Bet | $25 Bet | $50 Bet | $100 Bet | $500 Bet |
|---|---|---|---|---|---|
| +100 | $20 | $50 | $100 | $200 | $1,000 |
| +150 | $25 | $62.50 | $125 | $250 | $1,250 |
| +200 | $30 | $75 | $150 | $300 | $1,500 |
| +250 | $35 | $87.50 | $175 | $350 | $1,750 |
| +300 | $40 | $100 | $200 | $400 | $2,000 |
| -100 | $20 | $50 | $100 | $200 | $1,000 |
| -150 | $16.67 | $41.67 | $83.33 | $166.67 | $833.33 |
| -200 | $15 | $37.50 | $75 | $150 | $750 |
| -250 | $14 | $35 | $70 | $140 | $700 |
| -300 | $13.33 | $33.33 | $66.67 | $133.33 | $666.67 |
Common Mistakes {#mistakes}
Avoid these frequent errors when reading American odds.
Mistake 1: Confusing Positive and Negative
The Error:
Thinking +200 means you need to bet $200 to win $100
(That's actually -200!)
The Fix:
- Positive (+) = You win MORE than you bet (underdog)
- Negative (-) = You bet MORE than you win (favorite)
Memory Trick:
- Plus sign = Plus money in your pocket
- Minus sign = Minus money from your wallet
Mistake 2: Not Accounting for Stake
The Error:
Seeing +300 and thinking "$300 payout!"
Reality: $300 PROFIT + your $100 stake = $400 total
The Fix:
Always remember: Odds show profit, not total return.
+300 odds, $100 bet:
Profit: $300 ✅
Stake back: $100 ✅
Total: $400 ✅
Mistake 3: Misreading -110
The Error:
Thinking -110 means "bet $100, win $110"
Reality: Bet $110 to win $100
The Fix:
-110 is the standard vig on spreads/totals.
-110 odds:
Bet: $110
Win: $100
Total: $210
Mistake 4: Ignoring Implied Probability
The Error:
Betting -400 favorites because they're "safe"
Without realizing 80% probability means they lose 1 in 5 times
The Fix:
Convert odds to probability before betting.
-400 = 80% implied probability
That means 20% chance of losing!
Ask: "Is the risk worth the reward?"
$400 to win $100 = Need 80%+ to break even
Mistake 5: Not Shopping Lines
The Error:
Betting Chiefs -150 at Sportsbook A
When Sportsbook B offers Chiefs -135
The Fix:
Have accounts at multiple sportsbooks.
$100 on Chiefs -150 → Win $66.67
$100 on Chiefs -135 → Win $74.07
Difference: $7.40 per $100 bet
Over 100 bets: $740 difference!
Mistake 6: Chasing Negative Odds
The Error:
Building parlays with -300, -400, -500 favorites
"One loss ruins everything" + terrible risk/reward
The Fix:
Avoid extreme negative odds in parlays.
Bad Parlay:
-400 favorite × -350 favorite × -300 favorite
Combined: Still only +100 or so
One upset = entire parlay loses
Better:
Take the favorites straight (if you must)
Or find value in underdogs
FAQ {#faq}
Basic Odds Questions
Q: What does +200 mean in betting?
A: +200 means you win $200 profit for every $100 you bet. A $100 bet at +200 returns $300 total ($200 profit + $100 stake).
Q: What does -150 mean in betting?
A: -150 means you need to bet $150 to win $100 profit. A $150 bet at -150 returns $250 total ($100 profit + $150 stake).
Q: Why are some odds positive and some negative?
A: Positive odds (+) indicate underdogs (less likely, higher payout). Negative odds (-) indicate favorites (more likely, lower payout).
Q: What does -110 mean?
A: -110 is the standard “vig” on point spreads and totals. You bet $110 to win $100. It gives sportsbooks a ~4.5% edge.
Calculation Questions
Q: How do I calculate odds manually?
A: For positive odds: (Stake × Odds) ÷ 100 = Profit. For negative odds: (Stake × 100) ÷ |Odds| = Profit.
Q: What’s the formula for implied probability?
A: Positive: 100 ÷ (Odds + 100). Negative: |Odds| ÷ (|Odds| + 100). Multiply by 100 for percentage.
Q: How do I convert American odds to decimal?
A: Positive: (Odds ÷ 100) + 1. Negative: (100 ÷ |Odds|) + 1.
Strategy Questions
Q: Should I bet favorites or underdogs?
A: Bet based on value, not just who you think wins. If your estimated probability > implied probability, there’s value.
Q: Are negative odds safer?
A: Favorites win more often, but the payout often doesn’t justify the risk. A -500 favorite still loses 1 in 6 times.
Q: What’s the best odds format for beginners?
A: American odds are standard in the US, but decimal odds are easier to calculate. Most sportsbooks let you switch formats.
Q: Why do odds change?
A: Odds move based on betting action, injuries, weather, and other factors. Sportsbooks adjust to balance their books.
Conclusion
Understanding American odds is fundamental to sports betting success. Here’s what you need to remember:
Key Takeaways:
- Positive odds (+) = Underdog, win more than you bet
- Negative odds (-) = Favorite, bet more than you win
- +200 = $200 profit on $100 bet
- -150 = Bet $150 to win $100 profit
- Implied probability tells you the sportsbook’s estimated chance
- Shop around — odds vary between sportsbooks
- Calculate value — don’t just bet who you think wins
Next Steps:
- Use our Parlay Calculator for multi-bet payouts
- Read our Complete Sports Betting Guide for advanced strategies
- Compare Best Sportsbooks for the best odds
Remember: Odds are just one part of smart betting. Combine with proper bankroll management and responsible gambling practices.
About the Author
BonusEdge Editorial Team includes former sportsbook oddsmakers, professional bettors, and data analysts. We’ve analyzed millions of bets across major US sportsbooks to bring you accurate, actionable guidance.
Our Mission: Demystify sports betting odds and help bettors make informed decisions while promoting responsible gambling practices.
Last Review Date: April 2026
Next Scheduled Review: July 2026
Disclaimer
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