Matched betting calculator
The lay stake, liability and qualifying loss for a qualifying bet or a free bet.
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How it works
Back at the bookmaker and lay the same selection at the exchange. The calculator works out the lay stake that leaves the same result either way. Choose a standard, underlay or overlay lay.
Worked through
A £10 qualifying bet backed at 3.0 and laid at 3.1, beside a £10 free bet (stake not returned) backed at 5.0 and laid at 5.2. Both use 2% commission and a standard lay.
| It shows | Qualifying bet | Free bet |
|---|---|---|
| Lay stake | £9.74 | £7.72 |
| Liability | £20.45 | £32.43 |
| Qualifying loss | -£0.45 | £7.57 |
| Potential profit | -£0.45 | £7.57 |
The qualifying bet finishes on -£0.45 whether the back bet wins or loses: the cost of qualifying at these prices.
The free bet finishes on £7.57 either way, less than its £10 face value, because a stake-not-returned free bet pays only its winnings.
Questions
How is the lay stake calculated?
It balances both outcomes, so the result is the same whether the back bet wins or loses. For a qualifying bet the lay stake is (back odds × back stake) ÷ (lay odds − commission), with commission as a decimal (2% is 0.02). For a stake-not-returned free bet, (back odds − 1) takes the place of the back odds.
What is liability?
The amount the exchange holds when you place a lay bet: the lay stake multiplied by (lay odds − 1). It is what the lay loses if the back bet wins.
What do Underlay and Overlay do?
Underlay sizes the lay so the result is zero if the back bet loses, and takes the whole difference when it wins. Overlay does the reverse. On the qualifying bet above, Underlay lays £10.20 and finishes on -£1.43 if the back bet wins. Overlay lays £9.52 and finishes on -£0.67 if it loses.
What commission do I enter?
The rate the exchange charges on net winnings in that market, as a percentage. It is charged on the lay side only. Under a standard lay it changes both the lay stake and the qualifying loss.
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Related
- Bonus bet calculatorSize the lay for a bookmaker bonus paid on a win or a loss, with the bonus counted in.
- Sequential lay calculatorLay an accumulator one leg at a time, with the stake for each leg.
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For the prices themselves, see the Matched odds feed.
For over-18s. If gambling is affecting you, free and confidential help is at GambleAware and the National Gambling Helpline on 0808 8020 133.
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