Use the stake calculator below to work out what your lay stake should be at the betting exchange.

Free Bet 
Bet Amount Stake Forfeited   
Bookmaker (Back) 
OddsCommission %Return 
Betting Exchange (Lay) 
OddsCommission %Risk 
Back ProfitLay Profit
Lay Stake
Overall Profit

Use Betfair as your betting exchange and get a free £25 stake

Important - Check carefully before placing your bets
1) Make certain you are backing and laying the same outcome
2) Your lay stake should be £
3) You will need £ in your betting exchange account to cover this bet.
4) If this is a free bet, double check whether the stake is returned. Getting this wrong will make a big difference to your profit.


How to Use This Calculator

Enter the following information:
Bet amount - Your stake amount at the bookmaker, whether it is a free bet or a qualifier.

Stake Forfeited - If this is a free bet, check whether it is stake returned; if it is then use the same amount as the Bet Amount. If this is a qualifying bet, or the stake is not returned, enter 0.

Free Bet - Tick this box if you are placing a free bet.

Bookmaker (Back) Odds - The odds (in decimal format) being offered by the bookmaker.

Bookmaker (Back) Commission - This will almost always be 0%.

Betting Exchange (Lay) Odds - The odds (in decimal format) being offered by the betting exchange.

Betting Exchange (Lay) Commission - The commission payable to the betting exchange on winning bets. At BetFair the starting commission is 5%.

The calculator will work out the optimum lay stake to place at the Betting Exchange, and what your profit will be. If this is a qualifying bet the profit should be as close to 0 as possible. If it is a free bet you should be trying to get as close to the bet amount as possible.

The other fields, which are for information only, are:
Bookmaker (Back) Return - The profit from the bookmaker if your bet there wins.

Betting Exchange (Lay) Risk - The amount you will pay out if your bet at the betting exchange loses, i.e. your bet at the bookmaker wins.

Back Profit - The return from the bookmaker should your bet there win (back return - lay risk).

Lay Profit - The return from the betting exchange should your bet win there (lay stake - commission).