UUID v1 Regex for PHP

What this pattern does

This page provides a well-structured, multi-part regular expression for matching uuid v1, ported and verified for PHP. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. 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
// UUID v1
// ReDoS-safe | RegexVault — Web & Network > Misc

define('UUID_V1_PATTERN', '/^[0-9a-f]{8}-[0-9a-f]{4}-1[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/');

function validate_uuid_v1(string $input): bool {
    return (bool) preg_match(UUID_V1_PATTERN, $input);
}

// Example
var_dump(validate_uuid_v1("a8098c1a-f86e-11da-bd1a-00112444be1e")); // bool(true)

Test Cases

When to use this pattern

This pattern is drawn from the Web & Network > Misc 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

UUID v1 embeds the MAC address of the generating machine in the node field (last 12 hex chars) — a privacy concern. UUID v4 is preferred for security-sensitive identifiers.