Tmux

Terminal multiplexer. Default prefix is Ctrl-b; many operators rebind to Ctrl-a (the GNU Screen convention). In the tables below prefix stands for whichever you’ve bound; prefix <key> means “send the prefix, release, then press <key>”. Without the prefix, keystrokes go straight to the foreground program inside the pane.

tmux list-keys (tmux lsk) prints every active binding for the current key-table; prefix ? shows the same list in a pager inside tmux. Copy mode has its own key-table: tmux list-keys -T copy-mode-vi or -T copy-mode.

Sessions

The outermost concept, a workspace that survives disconnect. Most operator workflows keep one session per project, named so tmux attach -t NAME brings it back after SSH drops or a reboot.

Key / Command	Action
tmux	start an unnamed session (auto-numbered)
tmux new -s NAME	start a named session
tmux new -s NAME -d	start detached (background only)
tmux ls	list sessions
tmux attach / tmux a	attach to last session
tmux attach -t NAME	attach to a named session
tmux switch -t NAME	switch the current client to a session (from inside tmux)
tmux kill-session -t NAME	kill one session
tmux kill-server	kill the whole server (every session)
prefix d	detach from current session
prefix D	detach with chooser (tmux 3+)
prefix s	interactive session list / switch
prefix $	rename current session
prefix (	switch to previous session
prefix )	switch to next session
prefix L	switch to last (most recently used) session

Windows

The middle layer, equivalent to a browser tab inside a session. Each window is its own full-screen workspace; switching between windows is the fastest way to context-switch without losing state.

Key	Action
prefix c	create a new window
prefix ,	rename current window
prefix &	kill current window (with confirm)
prefix n	next window
prefix p	previous window
prefix l	last window (most recently used)
prefix 0 … prefix 9	switch to window N
prefix '	prompt for window index
prefix w	interactive window picker (session tree)
prefix f	find a window by text in its content
prefix .	move current window to a different index
prefix M-n	next window with activity / bell
prefix M-p	previous window with activity / bell

Panes

Splits inside a window, each running its own shell. Most operator workflows live in panes: editor in one, log tail in another, REPL in a third. Pane navigation and zoom are the bindings that get used most.

Key	Action
prefix %	split vertically (left / right)
prefix "	split horizontally (top / bottom)
prefix Up / Down / Left / Right	move between panes by direction
prefix o	cycle to the next pane
prefix ;	last (most recently used) pane
prefix q	flash pane numbers (then digit jumps to that pane)
prefix z	zoom current pane (toggle)
prefix x	kill current pane (with confirm)
prefix !	break current pane out to a new window
prefix {	swap with previous pane
prefix }	swap with next pane
prefix Space	cycle through layout presets
prefix M-1 … prefix M-5	apply a specific built-in layout
prefix Ctrl-Up / Down / Left / Right	resize pane by one cell
prefix M-Up / Down / Left / Right	resize pane by five cells
prefix t	show a large clock in current pane
prefix i	display pane info (size, PID, title)

Copy Mode

Tmux’s read-only mode for browsing scrollback and copying to the internal buffer. setw -g mode-keys vi switches to vi-style; emacs is the default. Enter (emacs) or y (vi) yanks the selection into the tmux paste buffer.

Common navigation (works in both modes)

Key	Action
prefix [	enter copy mode
q / Esc	exit copy mode
prefix ]	paste the most recent buffer
Page Up / Page Down	scroll one page
Ctrl-u / Ctrl-d	half-page up / down
/	search forward
?	search backward
n / N	next / previous match
g	jump to top of scrollback
G	jump to bottom of scrollback

Emacs-mode selection (default)

Key	Action
Ctrl-Space	start selection
Alt-w / Esc w	copy selection to buffer
Ctrl-w	copy and exit copy mode
Ctrl-g	clear selection without copying

Vi-mode selection (setw -g mode-keys vi)

Key	Action
v	start character-wise selection
V	line-wise selection
Ctrl-v	block (rectangular) selection
y	yank selection to buffer
Y	yank current line
Esc	clear selection without yanking
0 / ^ / $	move to start / first non-blank / end of line
w / b / e	word forward / back / end
H / M / L	top / middle / bottom of visible pane
f<c> / F<c>	find next / previous character c on line

Buffers (Paste Stack)

Tmux maintains a paste-buffer stack across the whole server. Selections from copy mode push to the top; prefix ] pastes the top buffer.

Key / Command	Action
prefix ]	paste the top buffer
prefix =	choose-buffer (interactive list + paste)
prefix #	list buffers in the status bar
tmux list-buffers	print buffers (CLI)
tmux show-buffer	print the top buffer
tmux save-buffer FILE	write the top buffer to a file
tmux load-buffer FILE	read a file into a new buffer
tmux set-buffer "text"	load a literal string
tmux delete-buffer	drop the top buffer
tmux paste-buffer	paste into the active pane (CLI form of prefix ])

Command Prompt

The escape hatch. prefix : opens a prompt that accepts any tmux command from man tmux. Useful when no binding exists, or when scripting tmux against itself.

Command (after prefix :)	Action
new-window -n NAME	new window with explicit name
split-window -h	split horizontally (left / right)
split-window -v	split vertically (top / bottom)
resize-pane -D 5	resize current pane down 5 cells
rename-session NAME	rename current session
swap-pane -D	swap with next pane
kill-pane -a	kill all panes except current
set -g status-position top	move the status bar to the top
source-file ~/.tmux.conf	reload config
display-message "text"	flash a message in the status bar
run-shell "cmd"	run a shell command without disturbing panes
capture-pane -p	dump current pane buffer to stdout
clock-mode	show the big clock
confirm-before -p 'kill server? (y/n)' kill-server	guarded server kill

Status / Display

Key	Action
prefix t	large clock
prefix ~	show recent messages
prefix ?	list every binding
prefix r	reload config (custom binding, common addition)
prefix M	clear marked pane
prefix m	mark current pane (for swap-pane / join-pane)

Mouse Mode

Enable with set -g mouse on. Tmux then intercepts mouse events to switch panes, drag-resize borders, and select text in copy mode. Hold Shift to bypass tmux and pass the click to the terminal (so the system clipboard / link handler still work).

Gesture	Action
Click pane	select pane
Click window	select window (status bar)
Drag border	resize pane
Right-click status	context menu (tmux 3+)
Right-click pane	pane menu (tmux 3+)
Scroll wheel	enter copy mode and scroll
Click + drag	select text in copy mode (auto-enters)
Shift + Click	bypass tmux; pass through to terminal

Config and Discovery

Command / file	Action
~/.tmux.conf	per-user config (legacy path)
~/.config/tmux/tmux.conf	per-user config (XDG path; tmux 3.1+)
/etc/tmux.conf	system-wide config
tmux source-file PATH	reload config without restarting
tmux list-keys / tmux lsk	list every binding (current key-table)
tmux list-keys -T copy-mode-vi	list copy-mode-vi key-table
tmux show-options -g	show global options
tmux show-window-options -g	show window-level globals
tmux show-environment	show session environment
tmux info	print server / build info
tmux -V	print version
tmux -CC	control mode (used by iTerm2 / Termux integrations)

Useful ~/.tmux.conf

A starter config that fixes the defaults most operators trip over: prefix on Ctrl-a, mouse mode on, vi copy mode, larger scrollback, and Vim-style pane navigation. prefix r reloads the file so changes take effect without restarting the server.

# Easier prefix
set -g prefix C-a
unbind C-b
bind C-a send-prefix

# Mouse mode
set -g mouse on

# Vi-style copy mode
setw -g mode-keys vi

# Renumber windows when one closes
set -g renumber-windows on

# Larger scrollback
set -g history-limit 10000

# Reload binding
bind r source-file ~/.tmux.conf \; display "Reloaded"

# Vim-style pane navigation
bind h select-pane -L
bind j select-pane -D
bind k select-pane -U
bind l select-pane -R