# Tmux Layouts

**Layouts** automatically arrange panes in a [[tmux-windows|window]] according to a preset pattern. Cycle through layouts with `Ctrl+B Space` to find one that fits your workflow.

Built-in layouts:

```
even-horizontal     panes arranged side-by-side, equal width
even-vertical       panes stacked vertically, equal height
main-horizontal     large main pane on top, smaller panes below
main-vertical       large main pane on left, smaller panes on right
tiled               fill window evenly, like a grid
```

Apply a layout:

```bash
$ tmux select-layout -t session:window layout-name
```

Cycle through layouts in the current window:

```
Ctrl+B Space        cycle to next layout
```

After manually arranging panes, apply a layout to lock the arrangement. For example, if you have 3 panes and apply `main-vertical`, the leftmost pane will be large and the two on the right will split the remaining space. When you resize the window, the layout proportions are maintained.

Switch layouts when you need a different pane arrangement without manually splitting or killing panes. Layouts are per-window—each window remembers its last-used layout.

Example: create a development layout with a main pane for editing and a pane below for the build output:

```bash
$ tmux new-window -n dev
$ tmux split-window -v -t dev -p 30         # bottom pane is 30% of height
$ tmux select-layout -t dev main-horizontal # lock the layout
```

The `main-horizontal` layout will maintain the main pane on top and the split pane below, even if you resize the terminal.