SPR in Poker: how to calculate and interpret it

Practice with exercises

Content by Tools of Poker Methodology and calculation assumptions

SPR formula: use the remaining effective stack

Stack-to-pot ratio (SPR) tells you how many pots fit into the remaining effective stack. It is commonly measured at the start of the flop, before any flop bets.

SPR = effective stack / pot
  1. At the start of the round, note the pot and the chips remaining behind. Do not include chips already in the pot in the remaining stack.
  2. For two players, use the smaller remaining stack. Divide it by the pot, using the same units for both.

Worked example: the pot is 20 bb. You have 120 bb left and your opponent has 80 bb. The effective stack is 80 bb, so SPR = 80 / 20 = 4, not 6.

Same pot, different stacks

Examples at the start of the flop with a pot of 20 bb.
effective stackpotSPR
40 bb20 bb2
80 bb20 bb4
160 bb20 bb8

At SPR 2 there are two pot-sized units left in the effective stack; at SPR 8 there are eight. This describes how much remains to be played for, not how strong your hand needs to be in every situation.

Check your calculation

The pot is 15 bb. You have 90 bb left and your opponent has 45 bb. What is the SPR?

min(90, 45) / 15 = 3

Common mistakes are using your own stack when the opponent has less, using the starting stack instead of the remaining stack, or mixing chips with big blinds.

What SPR cannot tell you

No. SPR measures stack depth relative to the pot, not hand strength. Consider the board, the opponent's range, equity, position and the price of the action before committing more chips.

For example, the same SPR with AA can accompany a very different decision on K-7-2 and on J-T-9. The opponent's actions and range matter; there is no universal SPR that makes a hand an automatic all-in.

Ready to test your understanding of Stack to Pot Ratio in real scenarios?

Start Stack to Pot Ratio Exercises

Frequently Asked Questions about SPR

No. SPR measures stack depth relative to the pot, not hand strength. Consider the board, the opponent's range, equity, position and the price of the action before committing more chips.

SPR compares the remaining effective stack with the existing pot. Pot odds compare the cost of a call with the final pot after that call. A low SPR does not automatically give you good pot odds.

The effective stack can differ for each opponent. Compare your remaining stack with each opponent's remaining stack and account for side pots; one SPR value may not describe the whole hand.