Bonus Bet Calculator — Free Bet Conversion Calculator
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Sportsbook promos hand out bonus bets (also called free bets) constantly, but they pay out winnings only — the stake is never returned. This calculator finds the hedge stake and guaranteed cash you'd lock in by betting the other side, so you know exactly what a promo is really worth before you use it.
Worked example: A $100 bonus bet at +200, hedged at -220, converts to $62.50 in guaranteed cash — a 62.5% conversion rate, with a $137.50 hedge stake.
FAQ
Why is a bonus bet worth less than its face value?
Because a bonus or free bet doesn't return your stake if it wins — you only collect the winnings. A $100 free bet at +200 wins $200, not $300, which is why converting it to cash always recovers less than 100% of its face value.
How is the conversion rate calculated?
We size a hedge bet on the opposing side so that the cash you end up with is identical whether the free bet or the hedge wins, then express that guaranteed cash as a percentage of the original bonus amount.
What's a realistic conversion rate?
It depends entirely on how close the hedge odds are to a fair mirror of the bonus bet's odds. Tighter, closer-to-even markets convert at a higher rate; lopsided or heavily vigged matchups convert lower.