Simple
Back-and-lay calculator
Use this for an ordinary qualifying bet or a free bet. Leave the optional lay-stake box empty to balance the two outcomes automatically.
Advanced
Choose a calculator
Each-way and extra-place calculator
Enter the stake per way, the bookmaker terms and the separate win and place lay odds. If the bookmaker pays more places than the exchange market, the extra-place-only result is shown as well.
Dutching and arbitrage calculator
Split one budget across two to twenty mutually exclusive outcomes. Add commission only where it applies. A market percentage below 100% indicates a theoretical arbitrage before penny rounding.
Odds converter
Convert decimal, fractional or American odds and see the implied probability.
All stakes and settlements are rounded to pennies. Exchange commission is modelled separately for each winning exchange market. Each-way calculations treat the win and place legs as separate bets. The extra-place result applies only when the bookmaker pays but the chosen exchange place market does not.
It cannot verify live odds, liquidity, account eligibility, promotion rules, deductions, dead heats, partial matches or how an operator settles a market. The operators' accepted bets and final settlements take precedence.
Clear answers
Matched betting calculator questions
What does a matched betting calculator do?
It works out the lay stake needed to offset a bookmaker bet at a betting exchange. It also shows the exchange liability and the net result if the selection wins or does not win.
Which free-bet type should I choose?
Choose stake not returned when the bookmaker keeps the free-bet token after a winning bet and pays only the winnings. Choose stake returned only when the offer specifically returns the token value as withdrawable cash. Check the offer terms rather than guessing.
What is lay liability?
Liability is the exchange money at risk if the selection wins. The calculator shows the balance required to cover it, rounded up to the nearest penny.
How does the each-way and extra-place calculator work?
It treats the win and place parts as separate bets, calculates a lay stake for each market and shows the combined result for a win, normal place or unplaced finish. If the bookmaker pays more places than the exchange market, it also shows the extra-place-only result.
What is dutching and how does the arbitrage calculator help?
Dutching divides one budget across mutually exclusive outcomes so their returns are as even as possible. The arbitrage calculator includes commission, displays the market percentage and identifies when the entered prices leave a positive result for every outcome before and after penny rounding.
Why can the two results differ by a few pence?
Lay stakes, liability and commission settle in pennies. The calculator uses the rounded lay stake to model each outcome honestly, so a small difference can appear even when the unrounded formula balances perfectly.

