Arbitrage Calculator
Find arbitrage opportunities and calculate guaranteed profit
Formula:Arb% = 1 - Σ(1/Odds)
Arbitrage Calculator
Find guaranteed profit opportunities
Outcomes
Arbitrage Found!
Guaranteed profit opportunity
Total Implied
87.92%
Arb Margin
-12.08%
Guaranteed Profit
$137
ROI
+13.74%
Stake Distribution
| Outcome | Sportsbook | Odds | Stake | Payout |
|---|---|---|---|---|
| Outcome 1 | Book A | +130 | $1,137 | |
| Outcome 2 | Book B | +125 | $1,137 | |
| Total | $1,000 | $1,137 | ||
Arbitrage opportunity found! Total implied probability is 87.92% (under 100%). By placing the stakes shown above, you'll profit $137 (13.74% ROI) regardless of which outcome wins. Place all bets quickly before odds change.
Try These Examples
Sample arbitrage scenarios
Arbitrage Bet Tracker
0 / 100 entries
Bet History
0 entries
No bets recorded yet.
Add your first bet to start tracking.
How Arbitrage Works
Understanding the mathematics
Arbitrage exists when the sum of implied probabilities across all outcomes is less than 100%. This creates a mathematical edge where betting all outcomes guarantees profit.
Example with +130 and +125 odds:
Implied 1: 1/2.30 = 43.48%
Implied 2: 1/2.25 = 44.44%
Total: 43.48% + 44.44% = 87.92%
Since 87.92% < 100%, arbitrage exists!
Quick Answer
Key concepts at a glance
Arbitrage exists when total implied probability < 100%. For 2-way: if odds are 2.10 and 2.10, implied = 47.6% + 47.6% = 95.2%. Since < 100%, a $1000 stake split proportionally guarantees profit. Formula: Stake = (Total × (1/Odds)) / Sum(1/Odds).
Key Facts About Arbitrage Betting
Important concepts to understand
- Arbitrage (arbing) guarantees profit regardless of the outcome
- Arb opportunities exist when sportsbook odds collectively imply <100% probability
- Typical arb margins are 1-5% - large margins are rare and close quickly
- Stakes must be placed at all involved sportsbooks simultaneously
- Many sportsbooks limit or ban accounts suspected of arbitrage betting
- Arb opportunities often last only minutes before odds adjust
- Line movement, bet limits, and execution timing are the main risks
- Professional arbers use software to scan thousands of markets in real-time
Frequently Asked Questions
Common questions about arbitrage betting
What is sports betting arbitrage?
Arbitrage betting (arbing) exploits differences in odds between sportsbooks to guarantee profit. By betting on all possible outcomes at different books, you can lock in a positive return regardless of result. It requires odds that collectively imply less than 100% probability.
How do I find arbitrage opportunities?
Compare odds across multiple sportsbooks for the same event. Calculate total implied probability - if it's under 100%, an arb exists. Professional arbers use scanning software like OddsJam, RebelBetting, or BetBurger. Manual arbing is slow and opportunities disappear quickly.
Why do sportsbooks limit arbers?
Arbing extracts guaranteed profit from sportsbooks without risk. Books identify arbers through betting patterns: always taking the best price, betting on unpopular markets, unusual stake sizes, and betting immediately when odds move. Most sharp books will limit winning accounts.
Is arbitrage betting legal?
Yes, arbitrage betting is legal in most jurisdictions. It's not illegal to place bets at multiple sportsbooks or to shop for the best odds. However, sportsbooks can refuse service or limit accounts, and their terms of service may prohibit bonus abuse related to arbing.
What is three-way arbitrage?
Three-way arbitrage applies to markets with three outcomes (e.g., soccer: home win, draw, away win). The same principle applies - if total implied probability is under 100%, you can bet all three outcomes proportionally for guaranteed profit. Three-way arbs are less common but can have larger margins.
What are the risks of arbitrage betting?
Main risks include: 1) Odds changing before all bets are placed, 2) Bet limits preventing full stake, 3) Account restrictions/bans, 4) Errors in calculating stakes, 5) Voided bets (canceled games, etc.). Execution speed and accuracy are critical.
How this works
Calculations follow the published mathematics of the game — combinatorics for cards, probability theory for dice, and expected-value accounting for wagers. Results are verified against independent references (primarily Wizard of Odds). No calculation here is an opinion or recommendation; it is arithmetic applied to the rules of the game.
What this tool can’t do
When to consult a professional
This tool computes probability and expected value. It is not a betting system and cannot predict the outcome of any individual wager. If gambling is causing problems for you or someone you know, call the National Problem Gambling Helpline at 1-800-GAMBLER.
Sources
- [1]Wizard of Odds — Michael Shackleford, ASAIndustrywizardofodds.comAccessed Apr 21, 2026
Actuary; widely cited casino-game probability reference. Used for house-edge and EV verification.
- [2]National Council on Problem GamblingOfficial sourcencpgambling.orgAccessed Apr 21, 2026
Responsible-gambling guidance and 1-800-GAMBLER helpline.
Joseph OrdunaFounder & Software Engineer
Full-stack software engineer specializing in embedded systems, web architecture, and AI/ML. Founder of Practical Web Tools. Built the gesture-controlled drone IP acquired by KD Interactive (Aura Drone, sold on Amazon).