What is the regex for whitespace only?

The regex pattern for whitespace only is `^\s*$`. This pattern validates empty string or only whitespace characters.

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^\s*$/;` and test with `regex.test(yourValue)`. It returns `true` if the value matches.

How do I use this regex in Python?

In Python, use `import re; re.match(r'^\s*$', value)`. The raw string prefix (`r`) prevents Python from interpreting backslashes as escape characters.

Is this regex case-sensitive?

By default, yes. To make it case-insensitive, add the `i` flag in JavaScript (`/^\s*$/i`) or use `re.IGNORECASE` in Python.

Regex for Whitespace Only

Regex Pattern

^\s*$

Empty string or only whitespace characters

Quick Answer

The regex pattern for whitespace only is `^\s*$`. Empty string or only whitespace characters. This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
(empty)	✓ Matches
	✓ Matches
\t\n	✓ Matches
hello	✗ No match
a	✗ No match

Code Examples

javascript

const regex = /^\s*$/;
const isValid = regex.test(value);

python

import re
pattern = r'^\s*$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^\s*$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^\s*$/', $value)) {
    echo "valid";
}

java

String pattern = "^\\s*$";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

Related Regex Patterns

Leading/Trailing Whitespace

Matches whitespace at the start or end (for trimming)

Email Address

Validates a standard email address format

Email (RFC 5322 Compliant)

RFC 5322 compliant email validation with label length limits

URL (HTTP/HTTPS)

Validates HTTP and HTTPS URLs

URL (Any Protocol)

Matches URLs with any protocol (http, https, ftp, ws, etc.)

Domain Name

Validates a domain name (no protocol)