Enter your total stake and decimal odds from different sportsbooks. This surebet calculator will split your stake so each outcome returns nearly the same payout.
What is an arbitrage bet?
Arbitrage betting (often called a surebet) is when you place bets on every possible outcome of an event at different odds, so you lock in a profit no matter what happens. It works because sportsbook prices can differ enough to create a pricing gap.
In plain terms, if the combined implied probability of all outcomes is below 100%, there is an arbitrage opportunity. Your job is to split your bankroll in the right proportions to secure the same payout across outcomes.
How this arbitrage betting calculator works
This calculator uses decimal odds and applies the standard surebet formula. It handles 2-way, 3-way, and 4-outcome markets.
- Step 1: Add your total stake.
- Step 2: Enter decimal odds for each outcome.
- Step 3: Click calculate to get stake allocation, payout, profit, and ROI.
Core formula
Let each decimal odd be O₁, O₂, ..., Oₙ. Compute:
- Implied sum = (1/O₁) + (1/O₂) + ... + (1/Oₙ)
- Arbitrage exists if implied sum < 1
- Equalized payout = Total Stake / implied sum
- Stake for outcome i = Equalized payout / Oᵢ
If implied sum is 0.98, you have a 2% margin before fees, limits, and execution errors.
Example: 2-way market
Suppose two books offer:
- Outcome A at 2.20
- Outcome B at 2.05
Implied sum = 1/2.20 + 1/2.05 = 0.94235. Because it is below 1, this is a valid arbitrage setup. If your total stake is $1,000, the calculator will split your stakes so either result returns nearly the same gross payout.
Why decimal odds matter
Arbitrage math is easiest in decimal format because payout is simply stake × odds. If your sportsbook uses American or fractional odds, convert them first:
- American positive: decimal = (odds / 100) + 1
- American negative: decimal = (100 / |odds|) + 1
- Fractional a/b: decimal = (a / b) + 1
Practical issues that reduce real-world profit
Even with perfect math, real betting environments can reduce or eliminate edge:
- Line movement: odds can change before you place all legs.
- Stake limits: books may cap maximum stake on one side.
- Rounding: cents rounding can create tiny payout differences.
- Commission/exchange fees: especially relevant on betting exchanges.
- Void rules: different books may settle edge cases differently.
Execution checklist for better arbitrage betting
Before placing bets
- Confirm all outcomes are covered (including draw in 3-way markets).
- Double-check event, market type, and start time match exactly.
- Verify max stake and currency conversion impacts.
While placing bets
- Place the more fragile leg first (the one likely to move).
- Use quick bet slips and pre-funded accounts.
- Avoid unnecessary delay between legs.
After placing bets
- Record expected payout and guaranteed profit.
- Track actual settlement and identify slippage causes.
- Review books with strict limits to adjust strategy.
Common mistakes beginners make
- Using mixed odds formats without converting correctly.
- Forgetting to include all outcomes in 3-way soccer markets.
- Ignoring terms like “regular time only” vs “to qualify”.
- Assuming every low implied sum is tradable at desired stake size.
Is arbitrage betting risk-free?
Mathematically, surebets are designed to be risk-free if every leg is placed and settled as expected. Operationally, there is still execution risk: one leg may fail, odds may shift, or rules may differ by operator. So it is best described as low-risk, process-dependent, not magically guaranteed in practice.