How do I insert a literal control character or special key in insert mode?

Explanation

When you need to insert a literal tab character despite expandtab being set, or embed a control character like ^M (carriage return) into your text, <C-v> in insert mode is the tool. It tells Vim to insert the very next keystroke literally, bypassing any mappings or special behavior.

How it works

• <C-v><Tab> — inserts a real tab character, even when expandtab converts tabs to spaces
• <C-v><Esc> — inserts a literal escape character (^[) into the buffer
• <C-v><CR> — inserts a literal carriage return (^M)
• <C-v>065 — inserts the character with decimal ASCII code 65 (the letter A)

The key point is that <C-v> suppresses Vim's interpretation of the next key. This is different from <C-v>u{hex} which inserts Unicode by code point.

Example

Suppose you have expandtab set but need a real tab in a Makefile:

# Before (cursor in insert mode in a Makefile)
build:
    echo "spaces here"

# Press <C-v><Tab> to insert a literal tab
build:
	echo "real tab here"

Tips

• On Windows or in terminals that intercept <C-v>, use <C-q> instead — it works identically
• Use :set list to visually distinguish literal tabs (^I) from spaces
• <C-v> followed by three digits inserts the character by its decimal byte value
• In the command line, <C-v> works the same way for inserting literal characters into search patterns or Ex commands