A surebet calculator checks whether the combined implied probability across odds from different bookmakers falls below 100%. When it does, an arbitrage opportunity exists and the calculator shows the exact stake for each outcome so the profit is the same no matter what happens.
Enter the decimal odds for each outcome from the best available bookmakers, set your total stake, and the calculator returns the stake per outcome, the arbitrage percentage, and your guaranteed profit.
How to Use the Surebet Calculator
- 1Select number of outcomes — 2-way (win/lose), 3-way (win/draw/lose), or more.
- 2Enter the best odds for each outcome — from different bookmakers. Example: Home win at 2.10 (Bet365), Away win at 2.05 (Betway).
- 3Enter your total stake — the combined amount you are prepared to bet across all outcomes.
- 4Check the result — if the arbitrage percentage is below 100%, place the recommended stake at each bookmaker immediately. Odds change fast.
The Surebet Formula: A Worked Example
You need to cover all outcomes at different bookmakers. To check for an arb, calculate the implied probability for each odds and sum them:
Implied probability formula
Implied probability = 1 ÷ Decimal odds
Example: 2-way match
Home win @ 2.10: 1 ÷ 2.10 = 47.6%
Away win @ 2.05: 1 ÷ 2.05 = 48.8%
Total = 47.6% + 48.8% = 96.4% → Arbitrage exists. Margin = 3.6%.
Stake per outcome
Stake for outcome = (Total stake × Implied prob) ÷ Total arb %
With €200 total: Home stake = (200 × 0.476) ÷ 0.964 = €98.75. Away stake = €101.25.
Guaranteed return: €98.75 × 2.10 = €207.38 or €101.25 × 2.05 = €207.56. Profit ≈ €7.45 regardless of result.
Common Mistakes That Turn Surebets Into Losses
- ✕Odds change before you place all legs. Surebet windows can close in seconds. Place the less liquid leg first to avoid being half-exposed.
- ✕Betting on different markets at each bookmaker. Both bookmakers must settle the same event under the same rules. Asian handicap at one and 1X2 at another is not a surebet.
- ✕Ignoring withdrawal and deposit fees. A 2% arb margin disappears if your bookmaker charges a 2% withdrawal fee. Factor all costs before placing.
- ✕Using maximum stake at one bookmaker repeatedly. Consistent maximum bets on arb opportunities is one of the fastest ways to get your account restricted or closed.
Frequently Asked Questions
What is a surebet and how does it work?
A surebet is an opportunity where odds from two or more bookmakers produce a combined implied probability below 100%. By placing a calculated stake on every outcome across those bookmakers, your return exceeds your total stake regardless of the result.
What arbitrage percentage is worth pursuing?
Most traders target opportunities with at least 1.5–2% margin. Below 1%, the odds can shift against you before all bets are placed, turning the arb into a loss. Higher margins (3%+) are more reliable but rarer and disappear faster.
Do bookmakers ban surebet users?
Yes. Bookmakers restrict accounts showing consistent arbitrage patterns. Varying stakes, avoiding maximum bets, and mixing in occasional recreational bets slows this down. A matched betting strategy alongside surebets reduces account exposure risk.
Can I use this calculator for 3-way markets?
Yes. Select 3 outcomes and enter the best odds for home win, draw, and away win from different bookmakers. The formula is the same: sum of implied probabilities must be below 100% for an arb to exist.
How is a surebet different from matched betting?
Arbitrage uses odds discrepancies between bookmakers. Matched betting uses bookmaker free bets and promotions, laying off risk on an exchange. Both guarantee profit but require different tools and account types.
Finding surebets manually across dozens of bookmakers is time-consuming. The Oddsmatcher scans for the best available odds automatically so you can focus on placing the bets.
