How to resize a pane in tmux
Hold the prefix, then Alt+arrow resizes in steps of 5, Ctrl+arrow by 1:
keysprefix + M-↑/↓/←/→ (by 5) · C-↑/↓/←/→ (by 1)
These bindings repeat
Resize keys are bound with the repeat flag: press the prefix once, then keep tapping the arrow within repeat-time (500ms default) — no need to re-press the prefix for every step.
The easy ways
With set -g mouse on you can simply drag pane borders. prefix z zooms a pane to full size, which is usually what you actually wanted. And resize-pane -x 50% sets an exact width when you know the proportions you want.
Or stop resizing manually
prefix Space cycles preset layouts (even columns, even rows, main + others, tiled) and select-layout -E spreads panes out evenly — often faster than nudging borders.
Related
Verified against tmux 3.6 · updated July 2026 · back to the full cheat sheet