The best basic strategy for blackjack involves making decisions based on your hand and the dealer's upcard to minimize the house edge. Generally, you should stand on 17 or higher and hit on 11 or less. If your hand is between 12 and 16, stand if the dealer has a 2-6 (since they are more likely to bust), but hit if the dealer has 7 or higher. You should double down on 11, 10 (if the dealer has 9 or lower), and 9 (if the dealer has 3-6). Always split Aces and 8s, but avoid splitting 10s and 5s. When the dealer has a weak card (2-6), you can split 2s, 3s, 6s, 7s, and 9s. If surrender is allowed, surrender 16 against a dealer’s 9, 10, or Ace, and surrender 15 against a dealer’s 10. Following these guidelines helps you make the mathematically optimal decision in each situation, reducing the house edge.