UTM (Urchin Tracking Module) parameters are tags added to the end of a URL that tell Google Analytics where traffic came from. The five standard tags are utm_source (e.g. newsletter), utm_medium (e.g. email), utm_campaign (e.g. spring_sale), utm_term (paid keywords), and utm_content (to A/B test links). They turn vague 'referral' traffic into precise campaign data.

utm_source, utm_medium, and utm_campaign are the three that matter most — Google Analytics needs source and medium to attribute the visit, and campaign to group it. utm_term and utm_content are optional and used mainly for paid search and link-level A/B testing.

No. Never add UTM parameters to links pointing within your own site. Doing so resets the visitor's original session attribution, making it look like all your traffic came from the internal link. Only use UTMs on external links pointing to your site.

Yes. utm_source=Facebook and utm_source=facebook are treated as two separate sources in Google Analytics, splitting your data. Always use lowercase consistently to avoid fragmented reports. This tool lowercases values automatically to keep your data clean.

Not if handled correctly. UTM URLs can create duplicate content if crawled and indexed, so always set a self-referencing canonical tag on the destination page. Google generally ignores UTM parameters for ranking, but the canonical prevents the parameterized URL from competing with the clean one.

utm_source is the specific origin (e.g. 'mailchimp', 'twitter', 'partner-site') while utm_medium is the marketing channel category (e.g. 'email', 'social', 'cpc', 'referral'). Source answers 'which exact place?' and medium answers 'what type of marketing?'

Yes — that's the point. Keep utm_campaign identical (e.g. 'black_friday_2026') across all your links, then vary utm_source and utm_medium per channel. Google Analytics will roll them all up under one campaign while still letting you compare which channel performed best.