Outs and the Rule of 2 and 4

This lesson helps you estimate your chance to improve fast without a calculator.

Outs are the cards left in the deck that make your hand stronger (or make you likely to win).

What is an out?

An out is a card that improves your hand to something you can continue with or win at showdown.

• Flush draw: usually 9 outs
• Open-ended straight draw: usually 8 outs
• Gutshot straight draw: usually 4 outs
• Two overcards (like AK vs 88 on a low flop): often 6 outs (but not always clean)

Counting outs (step-by-step)

1. Decide what hand you need to become strong enough.
2. Count how many cards make that happen.
3. Remove outs that are not reliable (dirty outs).

Dirty outs (the ones that lie to you)

Dirty outs are cards that look like they help you, but can still leave you losing.

Common reasons outs are dirty:

• You make a hand, but Villain can make a better hand (reverse implied odds).
• Your “out” completes an obvious draw that Villain is also drawing to, but higher.
• Your “out” improves you to a hand that still loses to a lot of Villain’s range.

Example: you have a low flush draw. A spade may complete your flush, but if Villain can have a higher flush, some of those outs are dirty.

The Rule of 2 and 4 (quick equity estimate)

This rule converts outs into an approximate chance to hit:

• With two cards to come (flop to river): outs × 4
• With one card to come (turn to river): outs × 2

It’s an approximation, but it’s good enough for fast decisions.

Examples of the Rule of 2 and 4

Flush draw on the flop

You have a flush draw with 9 outs.

• Flop to river: 9 × 4 = 36%
• Turn to river: 9 × 2 = 18%

Open-ended straight draw on the flop

You have an open-ended straight draw with 8 outs.

• Flop to river: 8 × 4 = 32%
• Turn to river: 8 × 2 = 16%

Gutshot on the flop

You have a gutshot straight draw with 4 outs.

• Flop to river: 4 × 4 = 16%
• Turn to river: 4 × 2 = 8%

Common draw outs (quick list)

• Flush draw: 9 outs
• Open-ended straight draw: 8 outs
• Gutshot: 4 outs
• Set to full house/quads (when board not paired): about 7 outs to improve by river (varies by board)
• Two pair to full house: 4 outs to boat up on the next card (varies by board)

When the Rule of 2 and 4 breaks down

The rule estimates how often you hit, not how often you win.

• If your outs are dirty, your real winning chance is lower.
• If you can also win by bluffing or making Villain fold, your real EV can be higher.
• In multiway pots, hitting may not be enough if stronger hands are possible.

Mini drill (daily, 5 minutes)

1. Look at your hand and the board.
2. Count outs.
3. Remove dirty outs.
4. Multiply by 4 (flop) or 2 (turn).
5. Compare to pot odds required equity.

Next step: Outs Drill

Start the Outs Drill to practice counting clean vs dirty outs and applying the Rule of 2 and 4 under time pressure.

Related lessons:

• Pot Odds (required equity)
• Implied Odds (future money and reverse implied odds)
• Poker Equity (equity vs ranges)