What is the regex for markdown heading?

The regex pattern for markdown heading is `^#{1,6}\s+.+$`. This pattern validates markdown heading (# to ######).

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^#{1,6}\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'^#{1,6}\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 (`/^#{1,6}\s+.+$/i`) or use `re.IGNORECASE` in Python.

Regex for Markdown Heading

Regex Pattern

^#{1,6}\s+.+$

Markdown heading (# to ######)

Quick Answer

The regex pattern for markdown heading is `^#{1,6}\s+.+$`. Markdown heading (# to ######). This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
# Title	✓ Matches
## Subtitle	✓ Matches
###### Deep heading	✓ Matches
### My Section	✓ Matches
#NoSpace	✗ No match
Not a heading	✗ No match
####### Too deep	✗ No match

Code Examples

javascript

const regex = /^#{1,6}\s+.+$/;
const isValid = regex.test(value);

python

import re
pattern = r'^#{1,6}\s+.+$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^#{1,6}\s+.+$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^#{1,6}\s+.+$/', $value)) {
    echo "valid";
}

java

String pattern = "^#{1,6}\\s+.+$";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

Related Regex Patterns

Markdown Link

Markdown inline link [text](url)

Markdown Image

Markdown inline image ![alt](src)

Markdown Bold

Markdown bold text (**text** or __text__)

Markdown Code Block

Markdown fenced code block opening/closing delimiter

camelCase Word

camelCase identifier (starts lowercase, no separators)

snake_case Word

snake_case identifier (lowercase with underscores)