The rule of 2 and 4 in poker
The rule of 2 and 4 is a quick way to estimate your chance of hitting a draw. Multiply your outs by 4 on the flop (two cards to come) or by 2 on the turn (one card to come). The result is roughly your percentage chance. It’s not exact, but it’s close enough for decisions at the table.
Examples
Section titled “Examples”| Draw | Outs | Flop (×4) | Exact | Turn (×2) | Exact |
|---|---|---|---|---|---|
| Flush draw | 9 | 36% | 35% | 18% | 20% |
| Open-ended straight | 8 | 32% | 31.5% | 16% | 17% |
| Gutshot | 4 | 16% | 16.5% | 8% | 9% |
| Two overcards | 6 | 24% | 24% | 12% | 13% |
| Combo draw | 15 | 60% | 54% | 30% | 33% |
When it’s less accurate
Section titled “When it’s less accurate”- With many outs (12 or more), “×4” overestimates. A common fix: multiply by 4, then subtract the number of outs above 8. For 15 outs: 60 − 7 = 53%, very close to the exact 54%.
- ×4 assumes you’ll see both cards. If your opponent might bet big on the turn, use the one-card number (×2) for your flop call.
Using it with pot odds
Section titled “Using it with pot odds”- Count your outs. See pot odds and outs.
- Estimate your chance with the rule.
- Compare with the share of the pot you must pay: call ÷ (pot + bet + call).
- If your chance is higher, calling is profitable. See expected value.
Example: turn, pot $50, opponent bets $25. You have 9 outs: about 18–20%. You must pay 25 ÷ 100 = 25%. Fold, unless implied odds make up the difference.
For exact numbers, see the poker odds cheat sheet and playing draws.
What is the rule of 2 and 4?
Section titled “What is the rule of 2 and 4?”Multiply your outs by 4 on the flop or by 2 on the turn to estimate your chance of hitting.
Is the rule of 2 and 4 accurate?
Section titled “Is the rule of 2 and 4 accurate?”It’s close for small numbers of outs; with many outs it overestimates on the flop.
How do you correct the rule with many outs?
Section titled “How do you correct the rule with many outs?”Multiply by 4, then subtract the number of outs above 8.
Should I use ×4 on the flop if my opponent may bet the turn?
Section titled “Should I use ×4 on the flop if my opponent may bet the turn?”Often it’s safer to use the one-card estimate (×2), because you may not see the river cheaply.