PokerSolver
PokerSolver/4-max · 80bb · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb/BB vs CO 4-bet 20.7bb

BB vs CO 4-bet 20.7bb

4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb (blinds 0.5/1bb, ante 0.16bb) · 80bb · CO opens 3bb, BB 3-bets to 9bb, CO 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 · 80bb · 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

494 of 1,326 combos get here
Fold 73.6%Call 9.7%All-in 79.84bb 16.7%
Tap a hand, or type one above, to see its exact mix.

What is the GTO play for the big blind (BB) when CO opens 3bb, BB 3-bets to 9bb, CO 4-bets to 20.7bb in 4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb at 80bb?

CO opens 3bb, BB 3-bets to 9bb, CO 4-bets to 20.7bb in 4-max · SB 0.5bb · ante 0.16bb · 5% rake, cap 4.8bb, 80bb: the big blind (BB) folds 73.6%, calls 9.7% and goes all-in 79.84bb 16.7%. Always call: AJs, QTs+. Always all-in 79.84bb: 99-KK, 77, 55, AKs, A5s, AKo. Mixed: AA, 88, 66, AQs, ATs, A3s, KTs+, T9s, 98s, 86s+, 76s, 65s, 54s.

Always fold
A7s-A8s, A4s, K2s-K9s, Q4s-Q8s, J3s+, T6s-T8s, 97s, 85s, 74s-75s, 64s, 43s, AQo, A7o-A8o, A5o, K9o+, JTo, T9o
Always call
AJs, QTs+
Always all-in 79.84bb
99-KK, 77, 55, AKs, A5s, AKo
Mixed
AA, 88, 66, AQs, ATs, A3s, KTs+, T9s, 98s, 86s+, 76s, 65s, 54s
Settings: 4-max · 80bb · 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, 80bb stacks, 5% rake capped at 4.8bb; no rake when no flop is dealt). Solver: HoldemResources Calculator (HRC) (HRC CI 24.98). 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.