tmux

tmux Terminal Multiplexer Manual & Cheat Sheet

tmux is a terminal multiplexer that allows you to create, access, and control multiple terminal sessions from a single screen. It lets you detach from sessions and reattach to them later, keeping your processes running in the background.

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Core Concepts

• Session: A collection of windows managed by tmux. Keeps running even when detached.
• Window: A single screen within a session (equivalent to tabs in a web browser).
• Pane: A rectangular division within a window running a separate pseudo-terminal.

Default Prefix Key: Ctrl + b (written below as Prefix). To execute any in-session command, press Prefix, release both keys, and then press the command key.

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Session Management (Terminal Commands)

Action	Command
Start new session	tmux
Start named session	tmux new -s <session-name>
List sessions	tmux ls (or tmux list-sessions)
Attach to last session	tmux a (or tmux attach)
Attach to named session	tmux a -t <session-name>
Kill named session	tmux kill-session -t <session-name>
Kill all sessions except current	tmux kill-session -a
Kill tmux server (all sessions)	tmux kill-server

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In-Session Shortcuts

Session Controls

Shortcut	Action
Prefix + d	Detach from current session
Prefix + (	Switch to previous session
Prefix + )	Switch to next session
Prefix + s	Interactive session selector (tree view)
Prefix + $	Rename current session

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Window Controls (Tabs)

Shortcut	Action
Prefix + c	Create new window
Prefix + ,	Rename current window
Prefix + w	Choose window from interactive list
Prefix + n	Move to next window
Prefix + p	Move to previous window
Prefix + 0–9	Select window by number
Prefix + &	Kill current window
Prefix + .	Move/re-number current window

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Pane Controls (Splits)

Shortcut	Action
Prefix + %	Split pane vertically (left / right)
Prefix + "	Split pane horizontally (top / bottom)
Prefix + Arrow Key	Move focus to adjacent pane
Prefix + ;	Toggle to last active pane
Prefix + o	Swap focus to next pane
Prefix + z	Toggle pane zoom (fullscreen / restore)
Prefix + x	Close/kill current pane
Prefix + {	Swap current pane with previous pane
Prefix + }	Swap current pane with next pane
Prefix + Space	Toggle preset pane layouts
Prefix + Ctrl + Arrow	Resize active pane in steps
Prefix + q	Display pane numbers (type number to focus)
Prefix + !	Convert pane into its own window

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Navigation & Copy Mode

1. Enter Copy Mode: Prefix + [
2. Move cursor using Arrow keys, PageUp/PageDown, or Vim keys (h, j, k, l) if enabled.
3. Start Selection: Press Space
4. Copy Selection: Press Enter
5. Paste Copied Text: Prefix + ]
6. Exit Copy Mode: q or Esc

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Configuration (~/.tmux.conf)

Customise tmux settings by creating or editing ~/.tmux.conf.

Recommended Starter Configuration

# Enable mouse support (clickable panes, windows, scrolling)
set -g mouse on
 
# Use Vi keybindings in copy mode (scrollback navigation)
set -g mode-keys vi
 
# Vim-style copy & paste bindings in copy mode
bind-key -T copy-mode-vi v send-keys -X begin-selection
bind-key -T copy-mode-vi y send-keys -X copy-selection-and-cancel
 
# Set split pane shortcuts to more intuitive keys
bind \\ split-window -h -c "#{pane_current_path}"
bind - split-window -v -c "#{pane_current_path}"
 
# Easy config reload shortcut
bind r source-file ~/.tmux.conf \; display "Config Reloaded!"
 
# Vim-style pane selection
bind h select-pane -L
bind j select-pane -D
bind k select-pane -U
bind l select-pane -R
 
# Enable 256-color support
set -g default-terminal "screen-256color"

To reload configuration without restarting tmux, run:

tmux source ~/.tmux.conf