Surebets Calculator.
Enter decimal odds and a total stake. We allocate stakes so every outcome returns the same amount — and confirm whether the bet is a genuine arbitrage.
Split the stake.
Verify the edge.
Drop odds in below. The tool distributes your stake proportionally to 1/odds so each outcome returns the same payout. If the inverse sum is below 1.000, you have a sure bet.
Enter decimal odds (> 1.00) and a total stake, then click Calculate.
How does the surebets calculator work?
This surebet calculator distributes your total stake proportionally to 1/odds for each outcome so that the payout is equal regardless of the result. If the sum of implied probabilities Σ(1/odds) is below 1, you lock in a guaranteed profit — an arbitrage or sure bet. For live opportunities ready to copy into the calculator, see the live sure bets board.
2‑way vs 3‑way surebets
Use 2‑way for markets with two outcomes (Over/Under, Asian handicaps, tennis match winner, MMA) and 3‑way for markets with three outcomes (1X2 in football). The calculator adapts the inputs and the stake split automatically.
Worked example
A 2‑way market with odds 2.10 and 1.95 and a €100 total stake. Implied probabilities: 1 / 2.10 ≈ 0.4762 and 1 / 1.95 ≈ 0.5128, summing to 0.9890 — below 1, so an arbitrage exists. The stakes are €48.15 and €51.85 (rounded); both outcomes return €101.11. Your guaranteed profit is €1.11 (≈ 1.11%).
Tips for using the calculator
- Always use decimal odds — convert American or fractional formats first.
- Place all legs as quickly as possible to reduce odds-movement risk.
- Round stakes to plausible amounts (€10, €25, €50) — pure decimal stakes look suspicious to bookmakers.
- Account for bookmaker fees, betting tax in your jurisdiction and potential account restrictions.
- If your bookmaker pays out only in another currency, convert using mid-market FX to avoid hidden margin loss.
What is a surebet?
A surebet (also called arbitrage bet, arb or sure bet) is a betting opportunity where the bookmakers' combined pricing of every outcome is below 100% — i.e. Σ(1/odds) < 1. By staking each outcome at the right ratio across different bookmakers, you lock in a guaranteed profit regardless of the result. Sure-bets.today scans 40+ bookmakers and lists every active surebet for free.
Surebets calculator — FAQ
What is a surebet (arbitrage bet)?
A surebet is an arbitrage opportunity where the sum of the implied probabilities (Σ(1/odds)) across all outcomes is below 1. By staking every outcome at the right ratio you guarantee a profit regardless of the result.
How do I use the surebet calculator?
Pick 2-way or 3-way, type the decimal odds and your total stake, then click Calculate. The tool splits the stake proportionally to 1/odds so every outcome returns the same payout.
Is the surebets calculator free?
Yes. The sure-bets.today surebets calculator is 100% free, requires no signup and works on desktop and mobile.
Does the calculator support 2-way and 3-way markets?
Yes — switch between 2-way and 3-way with one click. Inputs and the stake split adjust automatically.
Which odds format can I use?
Decimal odds only. Convert American (e.g. +150) or fractional (e.g. 3/2) odds to decimal before entering them. 3/2 = 2.50, +150 = 2.50, -150 = 1.667.
What does Σ(1/odds) below 1.000 mean?
It means the bookmakers' combined implied probability is below 100%, which is mathematically impossible for any fair market — i.e. a pricing error you can exploit. The smaller the value, the higher the arbitrage margin.
What if the profit is negative?
If Σ(1/odds) ≥ 1 there is no arbitrage. You either break even (exactly 1) or lose money (> 1) by covering every outcome. Wait for better odds or pick another market.
Can I round the calculated stakes?
Yes — rounding to whole-euro amounts is generally fine on tight arbs (≥0.5% margin). Confirm the final combined payout still exceeds your total stake after rounding.
Is the surebet calculator mobile-friendly?
Yes — the calculator is mobile-first. Inputs use the numeric keypad, results stack vertically on phones, and you can paste odds directly from any bookmaker app.
Where do I find live sure bets to use with the calculator?
Open the sure-bets.today live arbitrage board at /sure-bets — every row shows a live opportunity with the bookmakers, the odds and the recommended stake split, refreshed every 90 seconds.