How do I force any split command to open as a vertical split in Vim?

Explanation

Vim's :vertical modifier (abbreviated :vert) can be prepended to any Ex command that opens a split window to make it open as a vertical split instead of a horizontal one. This is especially handy when using commands that don't have a built-in vertical variant — such as :help, :diffsplit, or :sbuffer.

How it works

• :vert is a command modifier, not a standalone command — it alters how the next command behaves
• Any command that would normally create a horizontal split becomes a vertical split
• Works with built-in commands and plugin commands alike

Example

Open Vim help in a vertical split instead of horizontal:

:vert help text-objects

Open a numbered buffer in a vertical split:

:vert sb 3

Start a diff against another file in a vertical pane:

:vert diffsplit other_file.txt

Tips

• Combine with :topleft or :botright to control where the vertical split appears: :botright vert sb 5
• You can also use :horizontal (:hor) to force horizontal splits when the default would be vertical
• If you find yourself always wanting vertical splits for help, add autocmd FileType help wincmd L to your vimrc to automatically move the help window to the right