Lay bet (exchange) calculator
Calculate liability and profit for lay bets on Betfair-style exchanges
Calculate the liability and profit when laying a selection on Betfair, Smarkets or other betting exchanges.
What is lay betting?
On a betting exchange, you can back (bet for) or lay (bet against) any outcome. When you lay, you're acting as the bookmaker — accepting someone else's back bet. If their selection loses, you keep their stake. If it wins, you pay them out at the lay odds. Lay betting underpins Hedging strategies and most matched-betting workflows. Compare lay odds with back odds via Odds Converter to find arbitrage between exchanges and traditional books.
See also: Hedge calculator, Free bet conversion, Arbitrage calculator
How to use
- 1Enter the lay odds offered on the exchange.
- 2Enter the backer's stake (the amount you'd accept).
- 3See your liability (max loss) and net profit (if the lay wins).
Example: laying Real Madrid at 2.50
Someone wants to back Real Madrid at 2.50 with €100. You lay it. Your liability is €100 × (2.50 − 1) = €150 — the amount you must put up to cover their winnings if Madrid wins. If Madrid loses or draws, you keep their €100 stake (minus a typical 2-5% exchange commission, so net ~€95-98).
When to use
- Trading bets in-play (back high, lay low for guaranteed profit)
- Matched betting with free-bet promos
- Hedging large futures bets when odds shorten
Frequently asked questions
What is the Lay bet (Exchange) calculator?
On a betting exchange, you can back (bet for) or lay (bet against) any outcome. When you lay, you're acting as the bookmaker — accepting someone else's back bet.
How does the Lay bet (Exchange) calculator work in practice?
Someone wants to back Real Madrid at 2.50 with €100. You lay it. Your liability is €100 × (2.50 − 1) = €150 — the amount you must put up to cover their winnings if Madrid wins. If Madrid loses or draws, you keep their €100 stake (minus a typical 2-5% exchange commission, so net ~€95-98).
When should I use the Lay bet (Exchange) calculator?
Trading bets in-play (back high, lay low for guaranteed profit). Matched betting with free-bet promos. Hedging large futures bets when odds shorten.