How to Replace a Word in Vi or Vim (Find and Replace)

Vi and Vim replace text with the substitute command, :s. With one short command you can replace a word on the current line, throughout the whole file, in a range of lines, or one match at a time with confirmation. This guide explains the syntax, gives ready-to-use examples, and covers special characters, whole-word matching and undo. The commands work in vi, Vim and Neovim on Linux, macOS and Windows.

Quick Answer

Press Esc to make sure you’re in Normal mode, then type :%s/old/new/g and press Enter. This replaces every “old” with “new” in the whole file. Add c (:%s/old/new/gc) to confirm each change.

The Substitute Command Syntax

:[range]s/pattern/replacement/[flags]

• range: which lines to search. % means the whole file; nothing means the current line.
• pattern: the text (or regular expression) to find.
• replacement: the new text.
• flags: g = every match on each line (not just the first), c = confirm each, i = ignore case, I = match case.

Common Examples

Command	What it does
:s/old/new/	First match on the current line
:s/old/new/g	All matches on the current line
:%s/old/new/g	All matches in the file
:%s/old/new/gc	All matches in the file, asking each time
:10,20s/old/new/g	Lines 10 to 20
:.,$s/old/new/g	From the current line to the end
:%s/old/new/gi	Whole file, ignoring case
:%s/\<old\>/new/g	Whole words only (not “golden”)

Confirm Each Replacement

With the c flag, Vim highlights each match and asks replace with new (y/n/a/q/l/^E/^Y)?

• y replace this one, n skip it
• a replace all remaining, q quit
• l replace this one and stop

Replace in a Visual Selection

1. Press V (line-wise Visual mode) and move to select lines.
2. Type :. Vim fills in :'<,’>.
3. Complete it: :'<,’>s/old/new/g and press Enter.

Special Characters

• Slashes in paths: use a different delimiter, such as :%s#/usr/local#/opt#g.
• Characters with special meaning (. * [ ] ^ $ \) need a backslash in the pattern, for example :%s/1\.0/2.0/g.
• & in the replacement inserts the matched text: :%s/error/[&]/g turns “error” into “[error]”.
• Delete a word: leave the replacement empty, :%s/old//g.
• Replace with a new line: use \r in the replacement, :%s/, /,\r/g.

Quick Replace Without :s

• cw changes from the cursor to the end of the word. Type the new word and press Esc.
• Search with /old, change one match with cgn, type the new word, press Esc, then press . to repeat on the next match (Vim only).

Undo, Save and Quit

• u undoes the whole substitution; Ctrl + r redoes it.
• :w saves, :wq saves and quits, :q! quits without saving.

Replace Across Multiple Files (Vim)

:args *.txt
:argdo %s/old/new/ge | update

The e flag suppresses errors in files without a match, and update saves changed files. For quick batch edits outside the editor, sed -i ‘s/old/new/g’ file.txt does the same on Linux.

Frequently Asked Questions

Why did only the first word on each line change?

You left off the g flag. Add it to replace every match on each line.

How do I see how many matches there are first?

Run :%s/old//gn. The n flag counts matches without replacing.

Is it different in plain vi?

The basic :s syntax is the same. Some extras, like \< \> word boundaries, cgn and highlighting, are Vim features.

Summary

1. Press Esc.
2. Type :%s/old/new/g and press Enter.
3. Add c to confirm each change, or a range to limit lines.
4. Press u to undo, :wq to save.