UTM parameters are query string values appended to URLs to track marketing campaign performance. The 5 standard UTM parameters: utm_source (where traffic comes from — google, newsletter, twitter), utm_medium (how — cpc, email, social), utm_campaign (which campaign), utm_content (which ad variation), utm_term (search keywords). Our parser strips the URL, decodes URL-encoded values, and presents a clean breakdown. This is essential for QA-ing links before sending email campaigns or publishing ads.