Arbitrage Betting Calculator
Calculate arbitrage betting opportunities and guaranteed profits. Find sure bets across sportsbooks, determine optimal stake distribution for 2-way and 3-way markets, and calculate your risk-free profit percentage.
Tennis, NFL, NBA, or any event with two outcomes
= +120 American | Implied: 45.5%
= +110 American | Implied: 47.6%
Optimal Stake Distribution
Guaranteed Return
$1,074.42
Return Verification (Any Outcome)
| If Winner | Your Stake | Return | Profit |
|---|---|---|---|
| Outcome 1 | $488.37 | $1,074.42 | $74.42 |
| Outcome 2 | $511.63 | $1,074.42 | $74.42 |
Notice the profit is the same regardless of which outcome wins - this is the essence of arbitrage betting.
Unusually High Margin - Verify Odds!
A profit margin above 5% is rare and may indicate a "palpable error" (obvious mistake) in one sportsbook's odds. Bets placed on erroneous odds are often voided. Verify the odds are correct before betting.
How Arbitrage Betting Works
Arbitrage betting exploits pricing differences between sportsbooks. When the combined implied probability of all outcomes is less than 100%, a guaranteed profit exists.
Formula:
Arbitrage % = (1/Odds1 + 1/Odds2 + ...) - if < 100%, arb existsProfit % = (1 / Sum of Implied Probs) - 1Understanding Break-Even Stakes
The optimal stake distribution ensures equal profit regardless of outcome. Each stake is proportional to its outcome's implied probability divided by the sum of all implied probabilities.
Stake = Total Stake × (Implied Prob / Sum of All Implied Probs)This distribution guarantees the same return whether outcome 1, 2, or 3 wins.
Related Calculators
About This Calculator
"Is it really possible to guarantee a profit from betting?" Yes - and it's called arbitrage betting, or "arbing." By exploiting pricing differences between sportsbooks, you can bet on all possible outcomes of an event and lock in a profit regardless of who wins. It's not gambling - it's mathematics.
Arbitrage opportunities exist because different sportsbooks have different opinions on probabilities, and they update their odds at different times. When one book offers +150 on Team A while another offers -130 on Team B, the combined implied probabilities might add up to less than 100% - creating a guaranteed profit window. Professional arbers scan hundreds of markets daily, finding these inefficiencies before the books correct them.
Our Arbitrage Betting Calculator takes odds from 2 or 3 outcomes across different sportsbooks and instantly calculates whether an arbitrage opportunity exists. If it does, you'll see the exact stake distribution for each bet, the guaranteed profit percentage, and your total return - regardless of which outcome wins. We support both American and decimal odds formats.
Important reality check: True arbitrage opportunities typically yield 1-5% profit margins. Claims of higher returns are usually mistakes or scams. Books also limit or ban winning arbers - this is a short-term strategy, not a career.
How to Use the Arbitrage Betting Calculator
- 1**Select market type**: Choose between 2-way (moneyline, over/under) or 3-way (soccer match result, draw possible) betting markets.
- 2**Enter odds for each outcome**: Input the best odds you've found across different sportsbooks. Toggle between American (+150) and decimal (2.50) formats as needed.
- 3**Check for arbitrage**: The calculator instantly shows whether an arbitrage opportunity exists based on the combined implied probabilities.
- 4**Enter your total stake**: Input how much you want to invest across all bets. This is typically limited by the maximum bet each sportsbook allows.
- 5**Review stake distribution**: See exactly how much to bet on each outcome to guarantee the same profit regardless of result.
- 6**Calculate guaranteed profit**: View your profit percentage, dollar amount, and total return before placing any bets.
- 7**Verify odds before betting**: Odds change rapidly - always confirm the displayed odds are still available at each sportsbook before placing bets.
- 8**Place bets simultaneously**: Execute all legs of the arb as quickly as possible to avoid odds movement. Professional arbers use multiple devices or browser tabs.
Formula
Arbitrage % = (1/Odds1) + (1/Odds2) + ... (1/OddsN)To find an arbitrage opportunity, convert each outcome's decimal odds to an implied probability (1 divided by decimal odds), then sum them. If the total is less than 100% (or 1.00), an arbitrage exists. The profit percentage equals (1 - sum) / sum. For stake distribution, divide each outcome's implied probability by the total, then multiply by your total stake. This ensures equal profit regardless of outcome.
How Arbitrage Betting Works
The Basic Principle:
Arbitrage betting exploits the fact that different sportsbooks offer different odds on the same event. When the combined implied probabilities of all outcomes add up to less than 100%, a guaranteed profit exists.
Simple Example (2-Way Market):
Two sportsbooks offer different odds on a tennis match:
- Sportsbook A: Player 1 to win at +120 (2.20 decimal)
- Sportsbook B: Player 2 to win at +110 (2.10 decimal)
Converting to implied probabilities:
- Player 1: 1/2.20 = 45.45%
- Player 2: 1/2.10 = 47.62%
- Total: 93.07% (less than 100% = ARBITRAGE EXISTS)
The Profit Calculation:
With a total stake of $1,000:
- Bet on Player 1: $1,000 × (45.45% / 93.07%) = $488.37
- Bet on Player 2: $1,000 × (47.62% / 93.07%) = $511.63
If Player 1 wins: $488.37 × 2.20 = $1,074.41 (profit: $74.41) If Player 2 wins: $511.63 × 2.10 = $1,074.42 (profit: $74.42)
Guaranteed profit: 7.44% regardless of outcome
3-Way Arbitrage (Soccer Example):
| Outcome | Decimal Odds | Implied Prob |
|---|---|---|
| Home Win | 3.00 | 33.33% |
| Draw | 3.50 | 28.57% |
| Away Win | 2.80 | 35.71% |
| Total | - | 97.61% |
Total is under 100%, so arbitrage exists with 2.45% profit margin.
Finding Arbitrage Opportunities
Where Arbs Come From:
Arbitrage opportunities exist because:
- Different opinions: Sportsbooks have independent odds-making teams
- Timing delays: Some books adjust odds faster than others
- Regional biases: Local books may favor hometown teams
- Line shopping: Thousands of markets across dozens of books
- Promotional odds: Boosted odds for marketing purposes
Common Arbitrage-Rich Markets:
| Market Type | Arb Frequency | Typical Margin |
|---|---|---|
| Tennis (live) | Very High | 1-3% |
| Soccer (3-way) | High | 1-4% |
| NFL moneylines | Medium | 1-2% |
| NBA totals | Medium | 1-2% |
| Prop bets | High | 2-5% |
| Live betting | Very High | 1-5% |
Tools Arbers Use:
- Odds comparison sites: OddsPortal, OddsChecker, OddsBoom
- Arb-finding software: RebelBetting, BetBurger, OddStorm (paid)
- Betting exchanges: Betfair, Matchbook (for lay bets)
- VPNs: Access geo-restricted sportsbooks
- Multiple accounts: 10-50+ active sportsbook accounts
- E-wallets: Skrill, Neteller for fast deposits/withdrawals
Manual vs Automated Arbing:
| Approach | Pros | Cons |
|---|---|---|
| Manual | Free, learning experience | Time-consuming, few opportunities |
| Software | 100x more opportunities, alerts | $50-500/month, account bans faster |
| Betting exchange | No account limits | Lower odds, 2-5% commission |
Most successful arbers combine all three approaches.
Stake Calculation Formula
The Stake Distribution Formula:
For each outcome in an arbitrage bet:
Individual Stake = (Total Stake × Implied Probability) / Sum of All Implied Probabilities
Or equivalently:
Individual Stake = Total Stake / (Decimal Odds × Sum of Implied Probs)
Step-by-Step Calculation:
Example with $500 total stake:
- Outcome A: Decimal odds 2.10 (implied: 47.62%)
- Outcome B: Decimal odds 2.05 (implied: 48.78%)
- Sum of implied probabilities: 96.40%
Stake on A: $500 × (47.62% / 96.40%) = $247.00 Stake on B: $500 × (48.78% / 96.40%) = $253.00
Verifying Equal Returns:
| Outcome | Stake | Odds | Return | Profit |
|---|---|---|---|---|
| A wins | $247.00 | 2.10 | $518.70 | $18.70 |
| B wins | $253.00 | 2.05 | $518.65 | $18.65 |
Profit is equal (within rounding) regardless of outcome.
Profit Percentage Formula:
Profit % = ((1 / Sum of Implied Probs) - 1) × 100
Using our example: Profit % = ((1 / 0.9640) - 1) × 100 = 3.73%
Key Insight:
The lower the sum of implied probabilities, the higher the profit. Professional arbers typically look for opportunities where the sum is below 98% (2%+ profit). Arbs under 1% profit are often not worth the effort due to execution risk.
American vs Decimal Odds Conversion
Understanding Odds Formats:
Sports bettors encounter different odds formats worldwide. Our calculator supports both American and decimal odds for maximum flexibility.
Decimal Odds:
The simplest format - your total return for a $1 bet.
- Odds of 2.50 means $1 bet returns $2.50 ($1.50 profit)
- Odds of 1.50 means $1 bet returns $1.50 ($0.50 profit)
Implied Probability = 1 / Decimal Odds
American Odds:
Positive odds (+150): How much you win on a $100 bet
- +150 means $100 bet wins $150 (plus your $100 back)
Negative odds (-150): How much you must bet to win $100
- -150 means $150 bet wins $100 (plus your $150 back)
Conversion Formulas:
American to Decimal:
- If positive: Decimal = (American / 100) + 1
- If negative: Decimal = (100 / |American|) + 1
Decimal to American:
- If decimal >= 2.00: American = (Decimal - 1) × 100 (positive)
- If decimal < 2.00: American = -100 / (Decimal - 1) (negative)
Quick Reference Table:
| American | Decimal | Implied Prob |
|---|---|---|
| -300 | 1.33 | 75.0% |
| -200 | 1.50 | 66.7% |
| -150 | 1.67 | 60.0% |
| -110 | 1.91 | 52.4% |
| +100 | 2.00 | 50.0% |
| +110 | 2.10 | 47.6% |
| +150 | 2.50 | 40.0% |
| +200 | 3.00 | 33.3% |
| +300 | 4.00 | 25.0% |
Pro Tip: Always verify odds conversions, especially near even money where small differences matter most for arbitrage.
Risks and Limitations of Arbitrage Betting
This Is NOT Risk-Free Gambling:
While arbitrage betting guarantees mathematical profit, real-world execution carries significant risks:
1. Odds Movement (Palpable Errors)
The most common risk. If odds change between placing your first and second bet, you might:
- Lose the arbitrage opportunity entirely
- End up with a guaranteed loss ("middled")
- Get one bet cancelled as a "palpable error"
Mitigation: Place bets simultaneously using multiple devices/tabs.
2. Account Limitations and Bans
Sportsbooks hate arbers because they guarantee losses for the book. Warning signs include:
- Maximum bet limits reduced to $5-20
- Bonus offers withdrawn
- Account closure without explanation
Average arber account lifespan: 2-8 weeks of regular use.
3. Stake Rejection
Your calculated stake might be rejected due to:
- Maximum bet limits
- Insufficient liquidity
- Odds changed during bet placement
This leaves you with partial exposure, potentially creating a losing position.
4. Human Error
Common mistakes include:
- Betting on wrong outcome
- Miscalculating stake amounts
- Betting at wrong sportsbook
- Inputting wrong odds
One mistake can wipe out months of small arb profits.
5. Withdrawal and Payment Issues
- Sportsbooks may delay withdrawals for "verification"
- Some books have poor withdrawal limits
- Currency conversion fees eat into thin margins
- Tied-up capital reduces bankroll efficiency
Reality Check Table:
| Risk | Probability | Impact |
|---|---|---|
| Odds movement | High | Medium |
| Account limits | Certain | High |
| Stake rejection | Medium | Medium |
| Human error | Low | Very High |
| Payment issues | Medium | Low-Medium |
Bottom line: Arbitrage betting works, but it's a temporary strategy requiring significant capital, time, and organization. It's not passive income.
Example Scenarios: 2-Way and 3-Way Markets
Scenario 1: Tennis Match (2-Way)
You find the following odds for a tennis match:
| Sportsbook | Player | American | Decimal |
|---|---|---|---|
| DraftKings | Djokovic | +125 | 2.25 |
| FanDuel | Sinner | +100 | 2.00 |
Calculation:
- Djokovic implied: 1/2.25 = 44.44%
- Sinner implied: 1/2.00 = 50.00%
- Total: 94.44% < 100% = ARBITRAGE EXISTS
With $1,000 stake:
- Bet on Djokovic: $1,000 × (44.44/94.44) = $470.60
- Bet on Sinner: $1,000 × (50.00/94.44) = $529.40
Guaranteed profit: $58.82 (5.88%)
Scenario 2: Soccer Match (3-Way)
Premier League match with odds across three books:
| Outcome | Best Odds | Decimal | Book |
|---|---|---|---|
| Man City Win | +105 | 2.05 | Caesars |
| Draw | +280 | 3.80 | BetMGM |
| Arsenal Win | +210 | 3.10 | PointsBet |
Calculation:
- Man City: 1/2.05 = 48.78%
- Draw: 1/3.80 = 26.32%
- Arsenal: 1/3.10 = 32.26%
- Total: 107.36% > 100% = NO ARBITRAGE
This is why 3-way arbs are harder to find - three margins add up faster.
Scenario 3: Successful 3-Way Arb
Rare 3-way opportunity found:
| Outcome | Decimal Odds | Implied |
|---|---|---|
| Home | 2.90 | 34.48% |
| Draw | 3.60 | 27.78% |
| Away | 3.00 | 33.33% |
| Total | - | 95.59% |
With $2,000 stake:
- Home: $2,000 × (34.48/95.59) = $721.52
- Draw: $2,000 × (27.78/95.59) = $581.23
- Away: $2,000 × (33.33/95.59) = $697.25
Guaranteed profit: $92.21 (4.61%)
Regardless of outcome, you receive approximately $2,092.
Pro Tips
- 💡Always verify odds at both sportsbooks immediately before placing bets - odds can change in seconds and eliminate your arbitrage opportunity.
- 💡Place bets as simultaneously as possible using multiple browser tabs or devices to minimize odds movement risk.
- 💡Start with well-funded accounts at 10+ sportsbooks to access the most arbitrage opportunities and avoid being identified quickly.
- 💡Round your stakes to normal amounts ($25, $50, $100) rather than precise calculated figures that obviously indicate arbing.
- 💡Focus on high-liquidity markets (major leagues, popular events) where your bets are less likely to be scrutinized or rejected.
- 💡Keep detailed records of every arb bet including sportsbooks used, odds, stakes, and outcomes for tax purposes and performance tracking.
- 💡Avoid same-event arbs at the same sportsbook - many books will void or limit bets they identify as opposite sides of an arb.
- 💡Consider using betting exchanges like Betfair for the lay side of arbs - exchanges have no stake limits and welcome all bettors.
- 💡Never deposit more than you can afford to have frozen - sportsbooks may hold funds during account reviews.
- 💡Watch for "palpable error" clauses in terms of service - obviously mispriced odds can be voided, leaving you with one-sided exposure.
- 💡Vary your betting patterns occasionally with small recreational bets to appear less like a professional arber.
- 💡Have backup sportsbooks ready in case your primary option rejects your stake - this lets you complete the arb elsewhere quickly.
Frequently Asked Questions
Arbitrage betting (or "arbing") is a strategy where you bet on all possible outcomes of an event across different sportsbooks to guarantee a profit regardless of the result. It exploits pricing differences between bookmakers. Arbitrage betting is completely legal in most jurisdictions - you're simply placing legal bets at legal sportsbooks. However, sportsbooks strongly dislike it because they're guaranteed to lose money, so they actively try to identify and limit arbers. While not illegal, arbers risk having their accounts limited or closed. Some countries have specific gambling regulations, so always check your local laws.
