ZIP code regex PHP
ZIP code (US postal code) regular expression can be used to verify if a given string contains a valid ZIP code or extract ZIP code from a string. Supports both 5-digit and 9-digit (ZIP+4) formats.
ZIP code regex
A regular expression to test a string against ZIP code format:
"/^[0-9]{5}(?:-[0-9]{4})?$/"
Enter a text in the input above to see the result
Example code in PHP:
// Validate ZIP code
$zip_regex = "/^[0-9]{5}(?:-[0-9]{4})?$/";
echo preg_match($zip_regex, '80001'); // returns 1
echo preg_match($zip_regex, '80001-2222'); // returns 1
echo preg_match($zip_regex, '800010'); // returns 0
// Extract ZIP code from a string
$extract_zip_pattern = "/[0-9]{5}(?:-[0-9]{4})?/";
$string_to_match = 'My zip code is 80001';
preg_match_all($extract_zip_pattern, $string_to_match, $matches);
print_r($matches[0])// matches[0] is ['80001']
Notes on ZIP code validation and extraction
This ZIP code regex has several limitations:
- It only works for US ZIP codes. If you need to support other countries, you might need to have a separate regular expression for each one of them and execute it based on the country provided.
- It can not guarantee that ZIP code actually exists. For instance, 99999 is a correct format, but this ZIP code does not exist.
- The extraction method can generate false-positive extraction if a string contains multiple numbers.
