Part: Part Four - Pot Odds & Hand Analysis
The rule of 2 and 4
Pre-flop
It folds to you on the button with T♠9♠ after a middle-position raise - a hand that flops plenty of draws.
Opener makes it 600 (3 BB); you hold T♠9♠ on the button. Best?
WhyCall. A suited connector in position is a fine call against a single raiser - it flops draws you can play accurately with the math.
What happensYou call; the blinds fold. Pot: 1,500 (7.5 BB).
Flop
Flop: 8♦ 7♣ 2♥ - you flop an open-ended straight draw (any 6 or J), eight outs. He bets 900, so you call 900 to win 2,400 (~2.7-to-1, need ~27%).
Use the rule of 2 and 4 to estimate your equity, then compare to the price.
WhyRule of 4: with two cards to come, outs × 4 ≈ 8 × 4 = 32%. You need only ~27% for this price, so call. (On the turn you'd switch to the rule of 2 - outs × 2.) It's a fast way to turn outs into equity at the table.
What happensYou call. Pot: 3,300 (16.5 BB).
Turn
Turn: K♣ - a brick. Now only one card to come. He bets 2,400, so you call 2,400 to win 5,700 (~2.4-to-1, need ~30%).
Rule of 2 now: eight outs × 2 ≈ 16%. Facing this price, best?
WhyFold. With one card to come your eight outs are only ~16% (rule of 2), but the price needs ~30%, and you have little implied odds left. The same draw that was a fine call on the flop is a clear fold on the turn - your equity halved, but the price didn't.
What happensYou fold. The math flipped on the turn, and so did you.
The rule of 2 and 4 let you estimate equity in seconds: ~32% on the flop (call) and ~16% on the turn (fold). The same eight outs were worth half as much with one card to come.
Outs × 4 on the flop, outs × 2 on the turn ≈ your equity - recompute every street, because a draw is worth half as much with one card left.