PokerSolver
PokerSolver/4-max · 100bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb/BB vs SB 4-bet 20.7bb

BB vs SB 4-bet 20.7bb

4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb (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

4-max · 100bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bbChange game
Stacks (bb), if they differ
Pot 30.34bbYour cards?
9bb
20.7bb

Tap your two cards.

Big blind's range

766 of 1,326 combos get here
Fold 63.1%Call 25.5%All-in 99.84bb 11.5%
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 4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb at 100bb?

SB opens 3bb, BB 3-bets to 9bb, SB 4-bets to 20.7bb in 4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb, 100bb: the big blind (BB) folds 63.1%, calls 25.5% and goes all-in 99.84bb 11.5%. Always call: AA, 99, 55, ATs-AQs, K9s-KJs, K2s-K3s, Q9s+, J9s+, T8s+, 97s+, 86s+, 75s+, 64s+, 53s+, AJo-AQo, KQo. Always all-in 99.84bb: JJ-KK, 44, AKs, A6s, A2s-A4s, AKo. Mixed: TT, 66-88, 33, A5s, KQs.

Always fold
J2s-J3s, T2s-T5s, 93s-95s, 82s, 73s, 62s, 42s, 32s, A6o-A7o, A2o-A4o, K9o, K2o-K6o, Q5o-Q7o, J4o-J9o, T5o+, 97o+, 86o
Always call
AA, 99, 55, ATs-AQs, K9s-KJs, K2s-K3s, Q9s+, J9s+, T8s+, 97s+, 86s+, 75s+, 64s+, 53s+, AJo-AQo, KQo
Always all-in 99.84bb
JJ-KK, 44, AKs, A6s, A2s-A4s, AKo
Mixed
TT, 66-88, 33, A5s, KQs
Settings: 4-max · 100bb · 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, 100bb stacks, 5% rake capped at 4.8bb; no rake when no flop is dealt). Solver: HoldemResources Calculator (HRC) (HRC CI 24.66). 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.