SPR Calculator (Stack-to-Pot Ratio)

How much of a hand do you need to put all your chips in? Two questions, then the answer, and why. Stack-to-Pot Ratio: know when to commit your chips.

Example filled in: 100 behind and 10 in the pot on the flop. Change anything.

Step 1: How many chips can you lose in this hand?

The smaller stack between you and your opponent (the effective stack): nobody can win more than that from you.

Step 2: How big is the pot on the flop?

Total pot on the flop, after the betting before it. Chips, dollars or big blinds: the units cancel out.

Or pick a common pot, everyone 100 big blinds deep:

With the example filled in, put it all in withTwo pair

Your stack is 10.0 times the pot: a medium SPR. Put it all in with two pair or better, or a strong draw.

Low SPRMedium SPRHigh SPR041020+You: 10.0
Stack-to-pot ratio (SPR)10.0Medium SPR
Commit with: Two pair+, strong draws. Be cautious with one pair.Standard play. Need strong hands to commit full stack. Top pair is good for 1-2 streets of value.

Formula · effective stack ÷ pot on the flop. The zones are a rule of thumb.

Why

Each stack is one pot (10).

You have 100 behind and 10 in the pot, so your stack is 10.0 pots. That is a few big bets: one pair is worth a bet or two, and two pair or better is worth them all. At 4 pots or fewer, top pair would do; above 10, you would want a set.

The three zones
Low SPR (0 - 4)
Committed. Top pair = all-in worthy.
Medium SPR (4 - 10)
Standard. Need two pair+ to commit.
High SPR (10+)
Deep. Only commit with nuts/near-nuts.

The thresholds are the usual teaching ones, not a computed answer: how much of a hand is worth a stack also depends on the board, the opponent and position.

How SPR works

SPR is the effective stack divided by the pot when the flop comes: 100 ÷ 10 = 10.0. It tells you, before you see a card, how much of a hand you need to put the whole stack in.

With a low SPR there is little left to bet, so a hand like top pair is already worth a stack. With a high SPR there are several big bets left, and one pair rarely survives all of them.

You set the SPR with your preflop play: a 3-bet pot leaves a low SPR, a limped pot a very high one.

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