What is the regex for email username part?

The regex pattern for email username part is `^([a-zA-Z0-9._%+-]+)@`. This pattern validates extracts the local/username part of an email address.

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^([a-zA-Z0-9._%+-]+)@/;` 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'^([a-zA-Z0-9._%+-]+)@', 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 (`/^([a-zA-Z0-9._%+-]+)@/i`) or use `re.IGNORECASE` in Python.

Regex for Email Username Part

Regex Pattern

^([a-zA-Z0-9._%+-]+)@

Extracts the local/username part of an email address

Quick Answer

The regex pattern for email username part is `^([a-zA-Z0-9._%+-]+)@`. Extracts the local/username part of an email address. This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
user@example.com	✓ Matches
jane.doe+filter@domain.com	✓ Matches
test_123@site.io	✓ Matches
@missing.com	✗ No match
plaintext	✗ No match
no-at-sign	✗ No match

Code Examples

javascript

const regex = /^([a-zA-Z0-9._%+-]+)@/;
const isValid = regex.test(value);

python

import re
pattern = r'^([a-zA-Z0-9._%+-]+)@'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^([a-zA-Z0-9._%+-]+)@/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^([a-zA-Z0-9._%+-]+)@/', $value)) {
    echo "valid";
}

java

String pattern = "^([a-zA-Z0-9._%+-]+)@";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

Related Regex Patterns

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)

Email Domain Part

Extracts the domain part of an email address