Blackjack: When to Stand\n\n According to the basic single deck blackjack strategy, when the sum of the cards is from 12 to 16, the right decision is to stand, provided the dealer has 4, 5, or 6. Also, use this move when you have a high hand of 17 or more, while a hit is a suitable choice for a soft 17 or less.

In blackjack, the decision to stand with 12 against a dealer's 3 depends on the strategy you're using. In a basic strategy, it's generally recommended to hit, as the dealer's weak card suggests they might bust. However, using a more advanced strategy, like card counting, might alter this decision.