(C-x means ctrl+x, M-x means alt+x)

Prefix key

The default prefix is C-b. If you (or your muscle memory) prefer C-a, you need to add this to ~/.tmux.conf:

# remap prefix to Control + a
set -g prefix C-a
# bind 'C-a C-a' to type 'C-a'
bind C-a send-prefix
unbind C-b

I’m going to assume that C-a is your prefix.

Sessions, windows, panes

Session is a set of windows, plus a notion of which window is current.

Window is a single screen covered with panes. (Once might compare it to a ‘virtual desktop’ or a ‘space’.)

Pane is a rectangular part of a window that runs a specific command, e.g. a shell.

Getting help

Display a list of keyboard shortcuts:

C-a ?

Navigate using Vim or Emacs shortcuts, depending on the value of mode-keys. Emacs is the default, and if you want Vim shortcuts for help and copy modes (e.g. j, k, C-u, C-d), add the following line to ~/.tmux.conf:

setw -g mode-keys vi

Any command mentioned in this list can be executed as tmux something or C-a :something (or added to ~/.tmux.conf).

Managing sessions

Creating a session:

tmux new-session -s work

Create a new session that shares all windows with an existing session, but has its own separate notion of which window is current:

tmux new-session -s work2 -t work

Attach to a session:

tmux attach -t work

Detach from a session: C-a d.

Switch between sessions:

C-a (          previous session
C-a )          next session
C-a L          ‘last’ (previously used) session
C-a s          choose a session from a list

Other:

C-a $          rename the current session
C-a

Managing windows

Create a window:

C-a c          create a new window

Switch between windows:

C-a 1 ...      switch to window 1, ..., 9, 0
C-a 9
C-a 0
C-a p          previous window
C-a n          next window
C-a l          ‘last’ (previously used) window
C-a w          choose window from a list

Switch between windows with a twist:

C-a M-n        next window with a bell, activity or
               content alert
C-a M-p        previous such window

Other:

C-a ,          rename the current window
C-a &          kill the current window

Managing split panes

Creating a new pane by splitting an existing one:

C-a "          split vertically (top/bottom)
C-a %          split horizontally (left/right)

Switching between panes:

C-a left       go to the next pane on the left
C-a right      (or one of these other directions)
C-a up
C-a down
C-a o          go to the next pane (cycle through all of them)
C-a ;          go to the ‘last’ (previously used) pane

Moving panes around:

C-a {          move the current pane to the previous position
C-a }          move the current pane to the next position
C-a C-o        rotate window ‘up’ (i.e. move all panes)
C-a M-o        rotate window ‘down’
C-a !          move the current pane into a new separate
               window (‘break pane’)
C-a :move-pane -t :3.2
               split window 3's pane 2 and move the current pane there

Resizing panes:

C-a M-up, C-a M-down, C-a M-left, C-a M-right
               resize by 5 rows/columns
C-a C-up, C-a C-down, C-a C-left, C-a C-right
               resize by 1 row/column

Applying predefined layouts:

C-a M-1        switch to even-horizontal layout
C-a M-2        switch to even-vertical layout
C-a M-3        switch to main-horizontal layout
C-a M-4        switch to main-vertical layout
C-a M-5        switch to tiled layout
C-a space      switch to the next layout

Other:

C-a x          kill the current pane
C-a q          display pane numbers for a short while

Other config file settings

Force a reload of the config file on C-a r:

unbind r
bind r source-file ~/.tmux.conf

Some other settings that I use:

setw -g xterm-keys on