UTM checker
catch mistakes before they ship.

The one parameter every analytics tool requires. Without it, the visit falls back to referrer detection and your campaign label is lost.

utm_source appearing twice means tools keep one value — and which one varies by tool. Reports silently disagree.

utm_medium= with nothing after it creates "(not set)" rows that are impossible to clean up later.

Anything in the URL fragment never reaches analytics. UTMs must live in the query string, before the #.

"Email" and "email" are two different campaigns in GA4 and every major tool. Case splits data permanently.

utm_compaign instead of utm_campaign is invisible in the report — the click is counted, the label is gone.

Spaces encode as %20, are easy to mistype, and produce near-duplicate campaign rows.

Channel grouping keys on utm_medium; campaign comparison needs utm_campaign. Optional, but you'll want them.