How to split panes horizontally in tmux?
Quick Answer
To split a tmux pane horizontally (creating a pane below), press Ctrl+b followed by " (double quote). You can also use the command tmux split-window.
Ctrl+b+"
Detailed Explanation
Splitting panes is one of tmux's most powerful features, allowing you to view multiple terminal sessions side by side. A horizontal split creates a new pane below the current one, stacking them vertically.
Note on Terminology
tmux's terminology can be confusing: a "horizontal split" creates a horizontal line dividing panes vertically (one above the other). This is why some users prefer to use the term "split horizontally" to mean "create a horizontal divider."
Using keyboard shortcuts:
Ctrl+b "- Split current pane horizontally (create pane below)Ctrl+b %- Split current pane vertically (create pane to the right)
Using tmux commands:
Ctrl+b :then typesplit-window- Split horizontallyCtrl+b :then typesplitw- Shorthand for split-window
From the command line (outside tmux):
tmux split-window -t session:window.pane- Split specific pane horizontally
Useful options:
split-window -h- Split vertically (side by side)split-window -v- Split horizontally (explicit)split-window -p 25- New pane takes 25% of spacesplit-window -c "~/projects"- Set starting directorysplit-window "top"- Run command in new pane
Pro Tip
Create a custom key binding for splitting windows while staying in the same directory by adding these lines to your ~/.tmux.conf:
bind '"' split-window -c "#{pane_current_path}"
bind % split-window -h -c "#{pane_current_path}"