PokerSolver
PokerSolver/Heads-up · 100bb · SB 0.5bb · 5% rake, cap 3bb/BB vs SB 4-bet 20.7bb

BB vs SB 4-bet 20.7bb

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

Heads-up · 100bb · SB 0.5bb · 5% rake, cap 3bbChange game
Stacks (bb), if they differ
Pot 29.7bbYour cards?
9bb
20.7bb

Tap your two cards.

Big blind's range

718 of 1,326 combos get here
Fold 63.8%Call 27.6%All-in 100bb 8.7%
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 Heads-up · SB 0.5bb · 5% rake, cap 3bb at 100bb?

SB opens 3bb, BB 3-bets to 9bb, SB 4-bets to 20.7bb in Heads-up · SB 0.5bb · 5% rake, cap 3bb, 100bb: the big blind (BB) folds 63.8%, calls 27.6% and goes all-in 100bb 8.7%. Always call: AA, 99, 55-66, A7s-AQs, K9s-KJs, Q9s+, J9s+, T9s, 98s, 87s, 76s, 64s+, 54s, AQo, KQo. Always all-in 100bb: JJ-KK, AKs, A4s, AKo. Mixed: TT, 77-88, 22-44, A5s-A6s, A2s-A3s, KQs, K7s-K8s, Q8s, J8s, T7s-T8s, 97s, 86s, 75s, 43s, AJo, KJo.

Always fold
K6s, K2s-K4s, Q7s, Q2s-Q5s, J2s-J7s, T3s-T6s, 93s-96s, 84s-85s, 73s-74s, 63s, 52s-53s, ATo, A5o-A8o, A2o-A3o, K7o-KTo, Q9o+, J8o+, T8o+, 97o+, 87o, 76o
Always call
AA, 99, 55-66, A7s-AQs, K9s-KJs, Q9s+, J9s+, T9s, 98s, 87s, 76s, 64s+, 54s, AQo, KQo
Always all-in 100bb
JJ-KK, AKs, A4s, AKo
Mixed
TT, 77-88, 22-44, A5s-A6s, A2s-A3s, KQs, K7s-K8s, Q8s, J8s, T7s-T8s, 97s, 86s, 75s, 43s, AJo, KJo
Settings: Heads-up · 100bb · SB 0.5bb · 5% rake, cap 3bb (small blind 0.5bb, big blind 1bb, 100bb stacks, 5% rake capped at 3bb; before the flop, rake only after a 3-bet). Solver: HoldemResources Calculator (HRC) (HRC CI 14.45). 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: GGPoker regular cash NL2, NL10 (rake cap 2.5bb there, 3bb here).

Close: GGPoker regular cash NL50 (rake cap 2bb there, 3bb here).

Close: PokerStars cash NL10 (rake cap 5bb there, 3bb here; 4.25% rake there, 5% here; no rake when no flop is dealt there).

Close: PokerStars cash NL50 (rake cap 1.5bb there, 3bb here; no rake when no flop is dealt there).

Close: CoinPoker cash NL2, NL10 (rake cap 2.5bb there, 3bb here; only its tables without antes).

Close: CoinPoker cash NL50 (rake cap 2bb there, 3bb here; only its tables without antes).

Close: WPT Global cash NL10, NL20 (4% rake there, 5% here; no rake when no flop is dealt there; only its tables without antes).

Close: WPT Global cash NL100, NL200 (rake cap 2bb there, 3bb here; 4% rake there, 5% here; no rake when no flop is dealt there; only its tables without antes).

Close: Natural8 regular cash NL2, NL10 (rake cap 2.5bb there, 3bb here).

Close: Natural8 regular cash NL50 (rake cap 2bb there, 3bb here).

Close: ACR Poker cash NL10 (rake cap 5bb there, 3bb here; its page does not say whether pots that end before the flop are raked).

CoinPoker tables with antes: their own chart.

Rake sources: ggpoker.com/poker-games/texas-holdem (fetched 2026-10-31); Rush rake and preflop rake confirmed on our own GG exports (972 of 1,034 pots, 210 of 211); regular tables' preflop rule from natural8.com/en/poker/texas-holdem (same network, fetched 2026-10-31); pokerstars.com/poker/room/rake (fetched 2026-10-31); coinpoker.com/games/texas-holdem/ (caps and the preflop rule) and coinpoker.com/guides/poker-rake/ (5%), fetched 2026-10-31; wptglobal.com/poker/poker-table-rake (fetched 2026-10-31); natural8.com/en/poker/texas-holdem (fetched 2026-10-31; caps by players dealt in, 3-bet pots raked before the flop); acrpoker.eu/real-money/poker-rake-calculation/ (fetched 2026-10-31).

Rake: Wrong rake for GG: this solve caps the rake at 3bb, but GG caps heads-up NL200 at $1.50 (0.75bb). A solve with GG's cap is queued.