What Is Expected Value?
Expected value (EV) is the average amount you expect to win or lose on a decision over the long run. In poker, every bet, call, raise, and fold has an EV. Positive expected value (+EV) decisions win money over time. Negative expected value (-EV) decisions lose money. The goal is to make +EV decisions consistently.
The EV Formula
EV = (Win% x Amount Won) - (Lose% x Amount Lost)
If EV is positive, the play is profitable. If negative, it costs you money in the long run.
Worked Examples
| Scenario | Win% | Pot Won | Lose% | Cost | EV |
|---|---|---|---|---|---|
| Flush draw call on flop | 35% | $200 | 65% | $50 | +$37.50 |
| Gutshot call, pot-sized bet | 17% | $200 | 83% | $100 | -$49.00 |
| Bluff with 40% fold equity | 40% | $100 | 60% | $75 | -$5.00 |
In example 1, calling $50 to win $200 with a 35% flush draw is clearly +EV. In example 2, calling $100 with only a gutshot (17%) is significantly -EV. Example 3 shows a borderline bluff that loses $5 on average — not worth it.
EV and Pot Odds
Pot odds are directly connected to EV. When your equity exceeds the pot odds you're being offered, calling is +EV. When your equity is less than the pot odds, calling is -EV. The pot odds percentage is essentially your break-even EV point.
- Equity > Pot Odds -> +EV call. You win more often than you need to.
- Equity < Pot Odds -> -EV call. You don't win often enough to justify the price.
See the pot odds guide for the full breakdown, or try the calculator.
+EV Calling with Outs
On the flop, you have a flush draw with 9 outs. The pot is $120 and your opponent bets $40.
- Pot odds: $40 / ($120 + $40 + $40) = 20%.
- Your equity (rule of 4): 9 x 4 = 36%.
- 36% > 20% -> Calling is clearly +EV.
- EV ≈ (0.36 x $160) - (0.64 x $40) = $57.60 - $25.60 = +$32.00.
Every time you make this call, you gain $32 on average. Over hundreds of hands, these small +EV decisions compound into significant profit.
Why Results ≠ Decisions
Poker has variance. You can make a perfectly +EV call and lose. You can make a terrible -EV call and win. In the short term, results are noisy and unreliable. What matters is the quality of your decision — did you make the +EV play? If so, the math will reward you over time.
This is the fundamental mental shift that separates beginners from experienced players. Stop evaluating decisions by their outcome. Evaluate them by their expected value.
Next Steps
- Master pot odds — the practical application of EV at the table.
- Learn to count outs to estimate your equity in real time.
- Use the pot odds widget on the calculator to practice EV calculations.