Poker study / TableRival
Pot odds and equity: calculate the price of a call
There are 100 chips in the pot. Your opponent bets 50. How much equity does calling need to break even? In this simplified example: 25%. Here is why.
Pot odds and equity are different
Pot odds describe the price of calling relative to the pot. Equity is your hand’s expected share of the pot against particular opponent cards or a range, including ties. You can calculate pot odds from chip amounts. Equity requires assumptions about the opponent’s cards and possible runouts.
The pot-odds threshold does not tell you your hand’s equity. It gives you a number to compare that equity with under the stated assumptions.
How to calculate required equity
Assume two players, no rake and no further betting — for example, calling an all-in. Every amount in these exercises represents virtual chips.
Required equity = call amount ÷ pot after calling
C ÷ (P + B + C)
- P — the pot before the opponent’s bet.
- B — the opponent’s bet.
- C — the amount you must add now.
In our example, P = 100, B = 50 and C = 50. The pot after calling is 200, so the threshold is 50 ÷ 200 = 25%. At exactly this threshold, calling and folding have the same expected chip result measured from the decision point.
Before your call, there are 150 chips to win and the cost is 50. Pot odds can therefore also be written as 3:1. Be careful: 50 ÷ 150 is not the equity threshold. The threshold’s denominator includes your call.
Formula reference: MIT OpenCourseWare, Poker Theory and Analytics, “Basic Strategy”, slide 13. The examples and exercises below are original.
Three exercises: calculate before revealing
Each time, the pot before the opponent’s bet is 100. The opponent bets the stated amount and you must add the same amount to call. The previous section’s assumptions apply.
1. The opponent bets 25. What is the equity threshold?
Pot after calling: 100 + 25 + 25 = 150. Threshold: 25 ÷ 150 = about 16.7%. Pot odds are 5:1.
2. The opponent bets 50. What is the equity threshold?
Pot after calling: 100 + 50 + 50 = 200. Threshold: 50 ÷ 200 = 25%. Pot odds are 3:1.
3. The opponent bets 100. What is the equity threshold?
Pot after calling: 100 + 100 + 100 = 300. Threshold: 100 ÷ 300 = about 33.3%. Pot odds are 2:1.
What if we assume 30% equity?
This is an exercise assumption, not an analysis of a particular hand. Expected chip change relative to folding equals equity × pot after calling − call cost.
| Cost | Calculation | Result |
|---|---|---|
| 25 | 0.30 × 150 − 25 | +20 |
| 50 | 0.30 × 200 − 50 | +10 |
| 100 | 0.30 × 300 − 100 | −10 |
These are mathematical averages, not promises about an individual hand or recommendations to play for money.
When the calculation is not enough
If further bets are possible, comparing equity with this threshold does not settle the decision. Future costs, potential additional winnings and whether you can actually reach showdown matter too. In a tournament, survival can also matter beyond the number of chips.
First state the assumptions. Then calculate the price. Only then evaluate your hand against a reasoned opponent range. Practise identifying card changes in the guide to reading the flop and the turn.