How do you calculate lay betting liability?

Liability equals the backer's stake multiplied by (lay odds minus 1). For example, laying £5 at odds of 6.0 gives a liability of £5 × 5 = £25 — the maximum you can lose if the horse wins.

What is the break-even strike rate in lay betting?

Break-even strike rate is liability divided by (liability plus profit). It is the percentage of lay bets that must win just to break even. It rises quickly with the odds, which is why the 5–10 price band offers the best balance of achievable strike rate and manageable liability.

How much should I stake on a lay bet?

Keep your liability to 2–5% of your total bankroll per bet. With a £500 bankroll, that means a maximum liability of £10–£25. Divide that liability by (odds minus 1) to find your maximum backer's stake at a given price.

Home › Guides › Lay Betting Calculator

Lay Betting Calculator

Work out your liability, your profit after commission, and the break-even strike rate before you place a lay. Liability is the number that catches people out — check it every time.

Lay odds

Backer’s stake (£)

Commission (%)

Bankroll (£, optional)

Liability

£25.00

max you can lose

Profit if it loses

£4.75

after commission

Break-even strike

83.3%

lays must win above this

How the numbers work

When you lay, your stake isn’t what you risk — your liability is. The formulas:

Liability = backer’s stake × (lay odds − 1). Lay £5 at 6.0 and you’re risking £25 to win £5.
Profit if the horse loses = backer’s stake − commission (charged only on winning lays).
Break-even strike rate = liability ÷ (liability + profit). It’s the share of lays that must win just to stand still — and it climbs fast as odds rise.

That break-even number is the whole argument for the 5–10 price band. Push the odds into double figures and you need a punishing strike rate to survive a single loss. Drop below 5.0 and the profit is too thin to matter. Try it in the calculator: set the odds to 15 and watch break-even sail past 93%.

Staking rule of thumb: keep liability to 2–5% of your bankroll per bet. Even a verified 90% hit rate produces losing runs — sensible staking is what keeps you in the game when they arrive. The calculator flags when your liability breaches 5% of the bankroll you enter.

The calculator settles the maths. Picking which horse is the harder part — see how to pick horses to lay, or let the model do it and check the verified results.

Know your liability. Then know your horse.

DonkeyRadar finds the statistically weakest horse in every qualifying race and sends the signal before the off. Start free — no credit card required.

Create free account

Verified results · Lay betting strategy · How to lay on Betfair