PokerSolver
PokerSolver/5-max · 100bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb/SB vs BTN 3-bet 4bb

SB vs BTN 3-bet 4bb

5-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb (blinds 0.5/1bb, ante 0.16bb) · 100bb · CO opens 2bb, BTN 3-bets to 4bb · Small blind to act

5-max · 100bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bbChange game
Stacks (bb), if they differ
Pot 8.3bbYour cards?
0.5bb
1bb
2bb
4bb

Tap your two cards.

Small blind's range

1,326 of 1,326 combos get here
Fold 92%Call 1.6%Raise 9.2bb 3.1%All-in 99.84bb 3.2%
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 2bb, BTN 3-bets to 4bb in 5-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb at 100bb?

CO opens 2bb, BTN 3-bets to 4bb in 5-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb, 100bb: the small blind (SB) folds 92%, calls 1.6%, raises 9.2bb 3.1% and goes all-in 99.84bb 3.2%. Always all-in 99.84bb: AKs, AKo. Mixed: 55+, A3s-AQs, KJs+, K9s, K7s, QJs, AJo-AQo, KQo.

Always fold
22-44, A2s, KTs, K8s, K2s-K6s, Q2s-QTs, J2s+, T2s+, 92s+, 82s+, 72s+, 62s+, 52s+, 42s+, 32s, A2o-ATo, K2o-KJo, Q2o+, J2o+, T2o+, 92o+, 82o+, 72o+, 62o+, 52o+, 42o+, 32o
Always call
No hand plays this every time
Always raise 9.2bb
No hand plays this every time
Always all-in 99.84bb
AKs, AKo
Mixed
55+, A3s-AQs, KJs+, K9s, K7s, QJs, AJo-AQo, KQo
Settings: 5-max · 100bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb (small blind 0.5bb, big blind 1bb, an ante of 0.16bb from every player, 100bb stacks, 5% rake capped at 8bb; no rake when no flop is dealt). Solver: HoldemResources Calculator (HRC) (HRC CI 23.9). 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.