The house advantage in blackjack typically ranges between 0.5% and 2%, depending on the rules of the specific game and the player's skill level. This advantage comes from factors like the dealer acting after players (causing players to lose even if the dealer busts later) and rules on blackjack payouts, splitting, doubling down, or whether the dealer hits on soft 17. Proper strategy by players can minimize the house edge, but it always ensures a slight long-term advantage for the casino.