Professional License Number (US, Generic) Regex for PHP

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching professional license number (us, generic), ported and verified for PHP. Identity and credential patterns need both correctness and safety, since they're frequent targets for adversarial input. The snippet below is ready to drop into your PHP project — whether you're validating in a Laravel validator, a WordPress plugin, or a standalone PHP script.

Php Implementation

<?php
// Professional License Number (US, Generic)
// ReDoS-safe | RegexVault — Identity & PII > Professional Identity

define('PROFESSIONAL_LICENSE_NUMBER_US_GENERIC_PATTERN', '/^[A-Z]{2}[0-9A-Z]{5,15}$/');

function validate_professional_license_number_us_generic(string $input): bool {
    return (bool) preg_match(PROFESSIONAL_LICENSE_NUMBER_US_GENERIC_PATTERN, $input);
}

// Example
var_dump(validate_professional_license_number_us_generic("CA12345678")); // bool(true)

Test Cases

When to use this pattern

This pattern is drawn from the Identity & PII > Professional Identity category and carries a ReDoS-safe certification. That matters for PHP developers because especially relevant in PHP where PCRE backtracking limits can trigger silent failures on malicious input. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

Professional licenses (medical, legal, engineering, nursing) are state-issued in the US. Formats vary by profession and state. Combine with license type (MD, RN, JD, PE) for meaningful validation. Verify against state licensing board databases for active status.