Guru
Expected Value (EV)
What EV means: Expected value is the average long-run result of a decision if that same situation happened many times.
In blackjack terms: EV is usually shown in units (`u`) per unit bet. Positive EV means profit over time. Negative EV means loss over time.
Why it matters: One hand can always run hot or cold. EV tells you whether your process is strong, not whether one outcome was lucky.
Why EV Is Useful
Decision quality: EV helps you choose the action that makes the most money over time, even when short-term results vary.
Why win rate can mislead: A play can win slightly more often but still earn less overall if losses are larger or high-value opportunities are missed.
Bankroll discipline: Thinking in EV terms reduces tilt decisions and helps you avoid chasing recent outcomes.
Book strategy context: Basic strategy is fundamentally an EV-optimization framework for each player hand vs dealer upcard matchup.
Quick EV Example
| Line | EV | Interpretation |
|---|---|---|
| Stand EV | -0.56u | On average, you lose 0.56 units per 1 unit bet if you always take this line here. |
| Hit EV | -0.54u | This line still loses on average, but less than standing, so it is the better choice. |
| Difference | +0.02u | Long-run edge of choosing the stronger action in this exact spot. |