PokerSolver
PokerSolver/4-max · 250bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb/SB vs CO 4-bet 20.7bb

SB vs CO 4-bet 20.7bb

4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb (blinds 0.5/1bb, ante 0.16bb) · 250bb · CO opens 3bb, SB 3-bets to 9bb, CO 4-bets to 20.7bb · Small blind to act

4-max · 250bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bbChange game
Stacks (bb), if they differ
Pot 31.34bbYour cards?
9bb
1bb
20.7bb

Tap your two cards.

Small blind's range

236 of 1,326 combos get here
Fold 40.3%Call 48.6%Raise 45.54bb 11.1%All-in 249.84bb 0%
Tap a hand, or type one above, to see its exact mix.

What is the GTO play for the small blind (SB) when CO opens 3bb, SB 3-bets to 9bb, CO 4-bets to 20.7bb in 4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb at 250bb?

CO opens 3bb, SB 3-bets to 9bb, CO 4-bets to 20.7bb in 4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb, 250bb: the small blind (SB) folds 40.3%, calls 48.6% and raises 45.54bb 11.1%. Always call: TT-JJ, 33-88, AJs-AQs, 76s, 65s. Always raise 45.54bb: AA. Mixed: QQ-KK, 99, AKs, A8s-ATs, A4s-A5s, KJs+, QTs+, J9s+, T9s, 87s, AKo.

Always fold
A6s-A7s, A3s, K9s-KTs, K7s, Q9s, T8s, AQo, KQo
Always call
TT-JJ, 33-88, AJs-AQs, 76s, 65s
Always raise 45.54bb
AA
Mixed
QQ-KK, 99, AKs, A8s-ATs, A4s-A5s, KJs+, QTs+, J9s+, T9s, 87s, AKo
Settings: 4-max · 250bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb (small blind 0.5bb, big blind 1bb, an ante of 0.16bb from every player, 250bb stacks, 5% rake capped at 4.8bb; no rake when no flop is dealt). Solver: HoldemResources Calculator (HRC) (HRC CI 24.91). A jackpot fee on bigger pots is not in this solve, so lines that build big pots may be slightly too loose. Bet sizes are the solved ones; a size that is not here plays like the nearest one.

Fits exactly: no game we have checked.

Close: CoinPoker cash with antes NL50 (rake before the flop in 3-bet pots there, none here).

Rake sources: the ante from 93 of our own CoinPoker hands at $0.25/$0.50 with a $0.08 ante, played 2026-09-30; the caps and the preflop rule from coinpoker.com/games/texas-holdem/, fetched 2026-10-31.