Skip to content
Tools

Lay Betting Calculator

Calculate lay stakes, liability, and profit for Betfair/exchange bets. Includes back-to-lay converter and multi-lay calculator.

Presets
Odds format:

Lay Bet Inputs

$
%

Results

Enter lay odds to see your liability and profit.

Understanding Lay Betting

Lay Liability

Liability = LayStake × (LayOdds − 1). This is the amount you risk if the back side wins. Always ensure you have enough in your exchange account to cover your liability.

Lay Profit

Profit = LayStake × (1 − commission%). If your lay wins (the event does NOT happen), you receive the lay stake minus the exchange commission.

Back-to-Lay

Back at high odds early, then lay at shorter odds in-running. Optimal lay stake = (BackStake × BackOdds) / (LayOdds − commission). Locks in guaranteed profit if odds have shortened.

Commission Impact

Betfair charges 2 to 5% commission on winnings. This reduces your effective lay odds. Your effective lay price is 1 + (LayOdds − 1) / (1 − commission rate): at 3.00 with 2% commission you are really laying 3.04.

Exchange lay betting exposes you to the full liability of a bet. Never lay for more than you can afford to lose on that outcome.

Keep what you worked out.

A free account saves your bankroll plans, sessions and the results you run here, on every device. No card, no upsell.

Next

Goes with this. Lock in profit on an open bet by calculating the optimal opposite-side stake. Essential when your parlay is 1 leg away from hitting.

Open Hedge Bet Calculator →
Related tools