PokerSolver
PokerSolver/5-max · 100bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb/BB vs SB 4-bet 20.7bb

BB vs SB 4-bet 20.7bb

5-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb (blinds 0.5/1bb, ante 0.16bb) · 100bb · SB opens 3bb, BB 3-bets to 9bb, SB 4-bets to 20.7bb · Big blind to act

5-max · 100bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bbChange game
Stacks (bb), if they differ
Pot 30.5bbYour cards?
9bb
20.7bb

Tap your two cards.

Big blind's range

726 of 1,326 combos get here
Fold 65.2%Call 24.8%All-in 99.84bb 10.1%
Tap a hand, or type one above, to see its exact mix.

What is the GTO play for the big blind (BB) when SB opens 3bb, BB 3-bets to 9bb, SB 4-bets to 20.7bb in 5-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb at 100bb?

SB opens 3bb, BB 3-bets to 9bb, SB 4-bets to 20.7bb in 5-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 8bb, 100bb: the big blind (BB) folds 65.2%, calls 24.8% and goes all-in 99.84bb 10.1%. Always call: AA, AJs-AQs, KTs-KJs, QTs+, JTs, T8s+, 97s+, 86s+, 76s, 65s, 54s, 43s, KQo. Always all-in 99.84bb: JJ-KK, 66, AKs, A4s-A5s, A2s, AKo. Mixed: TT, 88, 55, ATs, A6s, A3s, KQs, AQo.

Always fold
T5s-T6s, T2s-T3s, 92s-95s, 82s-83s, 73s, A6o, A2o-A4o, K2o-K6o, Q4o-Q6o, J4o-J8o, J2o, T3o-T8o, 96o
Always call
AA, AJs-AQs, KTs-KJs, QTs+, JTs, T8s+, 97s+, 86s+, 76s, 65s, 54s, 43s, KQo
Always all-in 99.84bb
JJ-KK, 66, AKs, A4s-A5s, A2s, AKo
Mixed
TT, 88, 55, ATs, A6s, A3s, KQs, AQo
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.