Poker 101
Pot Odds: The Math That Wins You Money
The rule of 2 and 4, and how to know if a call is profitable.
The whole concept in one sentence
If the chance you'll win the hand is greater than the chance you have to pay to stay in, calling is profitable. That's it. Everything else is mechanics.
Pot odds in one formula
Pot odds = bet to call ÷ (pot + bet to call). Example: pot is $10, opponent bets $5. To call, you need to put in $5 to win $15. That's $5 / $20 = 25%. So if your hand wins more than 25% of the time, calling is +EV.
The rule of 2 and 4
When you have a draw (flush, straight, etc.), count your outs (cards that complete it):
- •On the flop with 2 cards to come → outs × 4 ≈ % to hit by river. (9 flush outs × 4 = 36% chance.)
- •On the turn with 1 card to come → outs × 2 ≈ % to hit on river. (9 outs × 2 = 18% chance.)
Putting it together
Flush draw on the flop = 36% to hit. If pot odds are < 36%, call. If pot odds are > 36% (opponent overbet), fold. This is how winning players make most postflop decisions.
Pot odds = cost / (pot + cost). Rule of 2 and 4: outs × 4 (flop) or × 2 (turn) ≈ % to hit. Call if equity > pot odds.
See unfamiliar terms? Check the full glossary.