How do I search and replace only whole words and not partial matches in Vim?

Explanation

How it works

In Vim's regular expressions, \< and \> are word boundary anchors:

• \< matches the beginning of a word.
• \> matches the end of a word.

When used in a substitute command, they ensure that only complete word matches are replaced, preventing accidental changes to substrings within larger words.

The syntax is:

:%s/\<word\>/replacement/g

This replaces every occurrence of the exact word word throughout the file, but will not touch wordy, sword, password, or any other string that merely contains word as a substring.

Example

Consider this code:

var = "hello"
variable = "world"
var_name = "test"
my_var = var

Running :%s/var/config/g without word boundaries would produce:

config = "hello"
configiable = "world"
config_name = "test"
my_config = config

The word variable was incorrectly changed to configiable. Instead, use word boundaries:

:%s/\<var\>/config/g

Result:

config = "hello"
variable = "world"
var_name = "test"
my_config = config

Only standalone occurrences of var were replaced. Note that var_name still changed because _ is not a word character in Vim's default definition, so var in var_name starts at a word boundary.

Tips

• Add the c flag (:%s/\<var\>/config/gc) to confirm each replacement interactively.
• The * command in normal mode searches with word boundaries by default, making it easy to verify matches before substituting.
• Word boundaries also work in search: /\<var\> finds only whole-word matches of var.