Regex Editor & Tester

This regex captures the value of a Google Click ID (gclid) URL parameter using a named capture group 'gclid'. It uses a positive lookbehind to locate text immediately after 'gclid=' and a lazy match that terminates at an ampersand, whitespace, or end of line, making it well-suited for extracting gclid values from URL query strings. Typical use cases include marketing analytics, Google Ads traffic tracking, and parsing click IDs from server logs or referrer URLs.