Learn the reason behind the move
What is insurance in blackjack?
Insurance is a separate bet on the dealer’s blackjack. It does not improve the cards in your original hand.
Separate the two bets
When offered against a dealer ace, insurance concerns the dealer’s hidden ten-value card. Your main hand still has its own result. The name can make it sound like general protection, but it is a distinct wager with its own price and payout.
Blackjack rules and actions ↗The break-even probability
For a wager paying 2:1 profit, a one-unit insurance stake has expected net 2p−(1−p)=3p−1. It breaks even at p=1/3. This is the mathematical threshold, not a claim that a particular shoe currently has that composition. The basic-strategy tool does not track removed cards.
Insurance is outside the hand lookup
The supplied basic-strategy reference declines insurance and even money. The hit-or-stand result evaluates the main hand after a dealer peek has ruled out blackjack. Do not add an insurance recommendation derived from a generic hand total.
Rule-dependent strategy reference ↗