Free Bet Calculator
Calculate the exact profit, lay stake, liability and efficiency from any SNR or SR free bet offer. Select your free bet type, enter the odds and hit Calculate.
Bookmaker
Back BetBetting Exchange
Lay BetYour Results
How to Use This Calculator
1. Select your free bet type
Choose SNR if your stake won't be returned if the free bet wins — most bookmaker free bets are SNR. Choose SR if your stake is returned on a win — SR bets are worth more.
2. Enter free bet size & back odds
Free bet size is the value of your token (e.g. £30). Back odds are the decimal odds at the bookmaker. For free bets, aim for higher odds (4.00–8.00) to maximise efficiency.
3. Enter lay odds & commission
Lay odds are the price on the exchange for the same selection — usually slightly higher than back odds. Commission defaults to 2% for Betfair; adjust if yours is different.
4. Place both bets exactly
Use the exact lay stake the calculator gives you — do not round it. Place the free bet at the bookmaker and the lay bet on the exchange simultaneously for the best odds match.
SNR vs SR — What's the Difference?
| Type | If Free Bet Wins | If Free Bet Loses | Typical Efficiency | Common With |
|---|---|---|---|---|
| SNR | Profit only returned (not stake) | Nothing returned | 75–85% | Most bookmakers |
| SR | Profit + stake returned | Nothing returned | 90–95% | Less common — higher value |