Most casino bonuses are -EV traps. This calculator shows you the true expected value accounting for wagering requirements, house edge, max bet limits, and game restrictions.
Expected Value (EV) = Bonus Amount - (Total Wagering Requirement × House Edge)
Most bonuses are -EV (negative expected value) because the wagering requirement forces you to risk more than the bonus is worth. A 40x wagering requirement on a $100 bonus means you must wager $4,000. At 4% house edge (96% RTP slots), you'll lose ~$160 on average to clear a $100 bonus.
Only take bonuses with +EV or close to breakeven. Casinos know most players won't do this math — that's how they profit.