Surebet calculator: 2-way and 3-way arb detector
1win holds a Curaçao 8048/JAZ licence and offers 40,000+ markets across 30+ sports. This surebet calculator checks 2-way and 3-way markets for guaranteed-profit opportunities and calculates the exact stake to place on each outcome. Register with promo code XLBONUS before you place your first surebet.
Surebet detector and stake calculator
How this calculator works
A surebet (also called an arb) occurs when the combined implied probabilities across all outcomes in a market fall below 100%. By distributing a stake across each outcome in proportion to their implied probability, you guarantee a profit regardless of result.
For a 2-way market: arb% = (1/o1) + (1/o2). For a 3-way market: arb% = (1/o1) + (1/o2) + (1/o3). If arb% is less than 1.00, a surebet exists.
Stake allocation for each outcome: stake_n = (total x (1/odds_n)) / arb%. This ensures that every outcome pays out the same total amount: total / arb%. The guaranteed profit is (total / arb%) - total.
For example: o1 = 2.20, o2 = 2.10, o3 = 3.60. Arb% = 0.4545 + 0.4762 + 0.2778 = 1.2085. This is above 1.00, so no surebet exists. But if o3 were 5.00, arb% = 0.4545 + 0.4762 + 0.2000 = 1.1307, still no surebet. For a surebet on a 3-way, you typically need all three outcomes to be generously priced simultaneously.
Finding surebets requires comparing prices across multiple bookmakers simultaneously. Real-time discrepancies are uncommon and short-lived because bookmakers adjust rapidly. The most common genuine surebets arise from promotional boosts or error prices that are slow to correct.
The calculator does not apply commission deductions. If one leg is placed at a betting exchange, the lay commission (typically 2-5%) must be factored in to determine whether the net surebet still holds. See the matched bet calculator for commission-aware calculations.
Why use it at 1win
1win prices 40,000+ markets competitively. When promotional odds boosts go live, this calculator lets you check instantly whether they create a surebet against the standard market. Register with XLBONUS to access all markets and promotions.
FAQ
How often do real surebets occur?
Genuine surebets across reputable bookmakers are rare and disappear within minutes of appearing. They are more common during major events when multiple bookmakers compete and errors or boosts create temporary discrepancies.
What is the minimum arb% that makes a surebet worthwhile?
Any arb% below 100% (less than 1.00 in decimal form) is technically profitable. However, after account for minimum stake rounding and time cost, most arbers target at least 1-2% guaranteed profit margin.
Do I need accounts at multiple bookmakers?
Yes. Surebets arise from price discrepancies between different bookmakers. A single bookmaker cannot offer a surebet against itself in a standard market.
Can I use this for in-play markets?
Yes, but in-play markets move quickly. You must be able to place both bets almost simultaneously. Price changes between placements can eliminate the arb or even create a loss.
Is surebet betting legal?
Surebet betting is legal but some bookmakers restrict accounts identified as arbers. Always check terms and conditions and be aware of potential stake limits.