Free betting calculator
Bonus bet calculator
Work out what a bonus or free bet is worth at the odds you choose, whether the stake comes back or not, and how much cash a bet on the other side would lock in.
Your bonus bet
Because the bonus stake usually isn't paid back, a bonus bet is worth more at longer odds. Expected value uses the price's implied chance, so it includes the sportsbook's margin. Read the offer's terms: minimum odds, expiry and wagering rules decide what it is really worth.
Calculations show hypothetical outcomes from the prices you enter. They do not predict results, and betting always involves risk.
How the value is worked out
If the bonus stake is not returned, a win pays only the profit: bonus x (decimal odds minus 1). The expected value at the price's own implied chance is that payout divided by the decimal odds. Longer odds keep more of the bonus's value, because the part you never get back (the stake) matters less.
Locking in cash with a hedge
Bet cash on the other side so both outcomes pay the same: cash stake = bonus payout / other side's decimal odds. The locked amount is the bonus payout minus that cash stake. The calculator shows it as a share of the bonus, often called the conversion rate. It relies on both bets being accepted and settled on the same rules.
Related guides
Common questions
What is a bonus bet worth?
Less than its face value, because the stake usually isn't returned. A $50 bonus bet at +300 pays $150.00 if it wins and is worth about $37.50 on average at that price.
Why use a bonus bet at long odds?
Because you only keep the winnings. At -200 a $50 bonus bet pays $25.00 and is worth about $16.67; at +300 it is worth about $37.50.
What does converting a bonus bet mean?
Betting the other side with cash so that you get the same amount whatever happens. With the bonus at +300 and the other side at -350, a $116.67 cash bet locks in about $33.33, 67% of the bonus.
Does this apply to every sportsbook's offer?
No. Offers differ in minimum odds, expiry, whether winnings must be wagered again and whether the stake is returned. Read the terms; the calculator only does the arithmetic.
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