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

BB vs BTN 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 · BTN opens 3bb, BB 3-bets to 9bb, BTN 4-bets to 20.7bb · Big blind to act

Fits exactlyno game we have checked
Close1 games
  • CoinPoker cash with antes NL50rake before the flop in 3-bet pots there, none here
4-max · 100bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bbChange game
Stacks (bb), if they differ
Pot 30.84bbYour cards?
9bb
20.7bb
0.5bb

Tap your two cards.

Big blind's range

580 of 1,326 combos get here
Fold 69.4%Call 19%All-in 99.84bb 11.6%
Tap a hand, or type one above, to see its exact mix.

What is the GTO play for the big blind (BB) when BTN opens 3bb, BB 3-bets to 9bb, BTN 4-bets to 20.7bb in 4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb at 100bb?

BTN opens 3bb, BB 3-bets to 9bb, BTN 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 69.4%, calls 19% and goes all-in 99.84bb 11.6%. Always call: 55, ATs-AQs, KTs+, Q9s+, JTs, T9s, 87s, 76s, 65s, 54s, AQo. Always all-in 99.84bb: JJ-KK, 77, AKs, A2s-A5s, AKo. Mixed: AA, 88-TT, 66, J9s, 98s, KQo.

Always fold
K2s-K9s, Q8s, Q4s-Q5s, J3s-J8s, T3s-T8s, 95s-97s, 85s-86s, 74s-75s, 64s, 52s-53s, ATo-AJo, A3o-A7o, KTo-KJo, Q9o+, J9o+, T8o+, 98o
Always call
55, ATs-AQs, KTs+, Q9s+, JTs, T9s, 87s, 76s, 65s, 54s, AQo
Always all-in 99.84bb
JJ-KK, 77, AKs, A2s-A5s, AKo
Mixed
AA, 88-TT, 66, J9s, 98s, KQo
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.

Rake sources for the games it fits: 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.