Odds, equity and theory
Stack-to-pot ratio (SPR) in poker
Definition
The effective stack divided by the pot on the flop; it shows how committed you are to the pot.
A low SPR (about 3 or less) means one pair or better is often enough to go all-in. A high SPR (above 10) calls for stronger hands, because losing a big stack with a pair is costly.
SPR depends on the preflop action: a 3-bet pot has a low SPR, while a single raised pot has a higher one.
Example
A 100 effective stack and a 20 pot on the flop gives an SPR of 5.