Matched Betting Calculator
Balance a back and lay bet to lock in a near risk-free return.
Use this matched betting calculator to keep qualifying losses small and lock in profit from stake-not-returned free bets. Enter the back odds from the bookmaker, the lay odds on the exchange and your commission rate to see the lay stake, liability and profit for each outcome.
How the calculation works
Core formula (qualifying bet): Lay Stake = (Back Stake × Back Odds) ÷ (Lay Odds − Commission)
Worked example: Back £10 @ 4.0, lay odds 4.2, commission 2% (0.02).
| Outcome | Back P/L | Lay P/L | Net |
|---|---|---|---|
| Back wins | +£30.00 | −£30.65 | −£0.65 |
| Lay wins | −£10.00 | +£9.38 | −£0.62 |
Lay stake = (£10 × 4.0) ÷ (4.2 − 0.02) = £9.57.
Always gamble responsibly. This calculator is for information only and does not guarantee profit.
Related tools
Which bet type should I choose?
Select qualifying for standard bets, free bet for stake-not-returned offers, or risk-free if the promo refunds as a free bet.
What is free bet retention?
Retention estimates how much of the free bet value you keep after laying it off on the exchange.
Do I need exchange commission?
Yes. Commission affects net profits, so include your rate for more accurate results.