What is the regex for password 12+ characters?

The regex pattern for password 12+ characters is `^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{12,}$`. This pattern validates at least 12 characters with uppercase, lowercase, and digit.

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{12,}$/;` 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-z])(?=.*[A-Z])(?=.*\d).{12,}$', 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-z])(?=.*[A-Z])(?=.*\d).{12,}$/i`) or use `re.IGNORECASE` in Python.

Regex for Password 12+ Characters

Regex Pattern

^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{12,}$

At least 12 characters with uppercase, lowercase, and digit

Quick Answer

The regex pattern for password 12+ characters is `^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{12,}$`. At least 12 characters with uppercase, lowercase, and digit. This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
MyPassword123	✓ Matches
LongEnough4Me	✓ Matches
TwelveChars1A	✓ Matches
Short1A	✗ No match
alllowercase1	✗ No match
ALLUPPER123	✗ No match

Code Examples

javascript

const regex = /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{12,}$/;
const isValid = regex.test(value);

python

import re
pattern = r'^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{12,}$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{12,}$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{12,}$/', $value)) {
    echo "valid";
}

java

String pattern = "^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d).{12,}$";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

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