What is a good button defense range vs an open?
The GTO solver Button defense range at 100bb re-raises 11.8%, calls 4.3%, and folds 83.9% of hands in the fixed spot below.
This button model faces a cutoff open with both blinds still to act. The button has position on the original raiser postflop. The chart shows how each authored model divides its response among calls, re-raises, and folds for the specified opening size.
The GTO solver chart is our CFR solver's 100bb ranges, with 2.5bb opens (3bb from the small blind). The other charts are the ranges Poker Shark's Arena opponents play, not recommendations for your own play. The Arena's GTO opponent is GTO-style: hand-written rules, a little tighter than a solver. The other types are modeled on real players. Percentages are how often each one takes each action.
Green is raise, blue is limp or call, and gray is fold. Each share fills that percentage of the cell. Raise includes all-in actions. The Arena charts specify no raise size. Use the hand lookup for exact percentages. These fixed snapshots do not expose a rake setting.
6-max, 100bb starting stacks, 0.5/1bb blinds. BTN faces a 2.5bb open from CO, with no callers. UTG, HJ folded. Players still to act may continue.
Quick tip: The chart covers a cutoff opener. An earlier-position opener or a different raise size can call for a different response.
Button defending range by the numbers
Fixed reference figures, independent of the chart selected above. First-in comparisons count raises only; defense comparisons count raises plus calls.
For comparison, the GTO solver Cutoff defense range continues 9.7% of hands at 100bb, 6.4 points tighter than this seat. Figures count combos: pairs weigh six, suited hands four, and offsuit hands twelve. The opener can differ between defense seats; check each chart’s context.
Now play the spots, not just the chart.
Practice against opponents whose ranges are too loose, too tight, or too passive, and exploit the gap.
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