SPR
SPR is the ratio of effective stack to pot at the start of the flop. It determines how much postflop room you have and the commitment threshold.
SPR (Stack-to-Pot Ratio) is the ratio of effective stack to the pot at the start of the flop. It determines the postflop room you have and how much commitment you can make.
Detailed Explanation
SPR formula:
SPR = effective stack at flop / pot at flop
Example: 100bb heads-up pot, open 3bb, opponent calls 3bb. Flop pot = 6.5bb (with blinds), effective stack = 97bb, SPR ≈ 15.
SPR-band strategic implications:
| SPR | Meaning | Strategy |
|---|---|---|
| < 4 | Low SPR (commit zone) | Top pair+ is usually committed; rarely fold top pair |
| 4-10 | Medium SPR | Balance cbet vs check; both value and bluffs have room |
| 10-20 | High SPR (standard heads-up pot) | Multi-street room, range thinking dominates |
| > 20 | Very high SPR (deep) | Top pair value is limited; need stronger combos to commit |
Low-SPR scenarios: 3bet pots, 4bet pots. Example: a 3bet pot's flop SPR is typically 3-5, so most of the time you decide commitment by the flop.
High-SPR scenarios: heads-up pots + multi-way pots. Deep cash pots (200bb+) can have SPR 50+, where committing on top pair is almost impossible.
Common Use Cases
- Choosing cbet sizing: low SPR → large size (toward commit), high SPR → flexible
- Top pair value assessment: low SPR → top pair is often +EV all-in; high SPR → top pair is more of a bluff-catcher
- 3bet pot decisions: SPR usually locks in the commitment range — fewer fancy plays
- Deep cash games: high SPR lowers relative top-pair value, raises the weight of strong combos (sets+)