LAUNCH WINDOW

Stack-to-pot ratio

SPR is the effective stack behind divided by the pot on the flop. It measures how much room is left to play.

SPR for common lines, using example bet sizes.

Line	Stack behind	Flop pot	SPR
100bb, open 2.5bb, big blind calls (SB folds)	97.5bb	5.5bb	17.7
100bb, open 2.5bb, button calls, blinds fold	97.5bb	6.5bb	15.0
100bb, 3-bet to 9bb from the big blind, button calls	91bb	18.5bb	4.9
100bb, 4-bet to 22bb, called	78bb	45.5bb	1.7
40bb, open 2.5bb, big blind calls	37.5bb	5.5bb	6.8
200bb, open 3bb, big blind calls	197bb	6.5bb	30.3

How far a stack reaches.

Stack needed, in starting pots, to bet and be called on each street.

Bets	SPR needed
1 street of pot-size bets	1
2 streets of pot-size bets	4
3 streets of pot-size bets	13
1 street of half-pot bets	0.5
2 streets of half-pot bets	1.5
3 streets of half-pot bets	3.5

Three pot-size bets need an SPR of exactly 13. Three half-pot bets need only 3.5.

Bands players often quote.

Low SPR (roughly under 4) leaves little room to fold a strong one-pair hand. Medium is about 4–10. High is above about 10. These bands are common guidance, not a law of the deck.

A 100-big-blind single-raised pot leaves an SPR near 18; a 4-bet pot leaves about 1.7. — Example bet sizes. The low, medium and high bands are a common rule of thumb, not a law of the deck. Open full-size chart ↗

These counts are for study and post-session review. Where a row comes from a simulation, the caption names how many deals were run. Where a stack or a pot is made up, the caption says so. None of these figures is an instruction for a live pot.

How far a stack reaches.

How much room is left after the flop