Turn your sportsbook bonus bets (free bets) into real, guaranteed cash with the PromoGrind Bonus Bet Converter.
A bonus bet — also called a free bet — is a credit awarded by a sportsbook that lets you place a wager without risking your own money. The key difference from a real cash bet: if you win, you receive the profit only — your original stake is not returned. A $100 bonus bet on +300 odds returns $300 in profit, not $400.
Because the stake is not returned on a win, using a bonus bet on a heavy favorite is inefficient — you win very little. The smarter play is to bet the bonus on an underdog and place a smaller cash bet on the opposing side at another book. This locks in a guaranteed profit regardless of which outcome wins, a technique called bonus bet conversion or free bet hedging.
The underdog's odds determine your conversion rate — the percentage of the bonus bet's face value you keep as guaranteed profit. The +250 to +400 range consistently produces the best conversion rates, typically between 65% and 75%. At +250, a $100 bonus bet converts to roughly $67 in guaranteed cash. At +400, it converts to approximately $73. Going too short (e.g., +130) or too long (e.g., +800) reduces efficiency significantly.