Regex for Visa Credit Card

javascript

const regex = /^4[0-9]{12}(?:[0-9]{3})?$/;
const isValid = regex.test(value);

python

import re
pattern = r'^4[0-9]{12}(?:[0-9]{3})?$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^4[0-9]{12}(?:[0-9]{3})?$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^4[0-9]{12}(?:[0-9]{3})?$/', $value)) {
    echo "valid";
}

java

String pattern = "^4[0-9]{12}(?:[0-9]{3})?$";
boolean isValid = value.matches(pattern);