UTM Parameters

Last updated 28 October 2026

Quick answer

UTM parameters are query parameters added to a URL so analytics can name the campaign behind a visit. A link such as ? In A/B testing, it helps teams connect a term, metric, or behavior to a clearer optimization decision.

Key takeaways

A UTM parameter is a query string on a link, such as utm_source or utm_medium, that labels where the click came from.
The five common fields are source, medium, campaign, term, and content.
Building or copying a template is a different job. That lives on the UTM template page.

Definition

UTM parameters are query parameters added to a URL so analytics can name the campaign behind a visit. A link such as ? utm_source=newsletter&utm_medium=email&utm_campaign=spring tells the analytics tool that this click came from the spring email.

What UTM Parameters means in A/B testing

UTM stands for Urchin Tracking Module, the tagging style Google Analytics inherited. Five fields cover almost every link. utm_source is the site or list, such as google or the newsletter. utm_medium is the channel, such as cpc, email, or social. utm_campaign is the promotion. utm_term is often the paid keyword. utm_content separates two creatives in the same campaign. Anything else in the query string is not a UTM parameter, even if it is useful for ads.

Why UTM Parameters matters

An experiment on a landing page is hard to read if paid and email traffic are dumped into one bucket. UTM parameters are how those buckets are labeled before the test starts. They are not the test. They do not assign a variant. They tell you which acquisition path a visitor was on, so a lift can be checked by source instead of only in total.

Example of UTM Parameters

The same pricing URL is used in a newsletter and in a paid search ad. The newsletter link ends in utm_source=newsletter&utm_medium=email&utm_campaign=april . The ad link ends in utm_source=google&utm_medium=cpc&utm_campaign=april . Both land on one page. Analytics can separate the two. Building those strings from ad-platform macros, for many campaigns at once, is what the template page is for.

How to use UTM Parameters

Pick one spelling for each source and medium and write it down. Put the tags on the links you control, not on internal navigation, or you will overwrite the original source. Check a tagged link in analytics before the campaign spends. When the job is "give me the template," leave this definition and open the UTM template .

Common mistake

A common mistake is tagging every internal button. The second click then looks like a new campaign and the original source disappears. Another is inventing a new parameter name, such as utm_channel , and expecting a standard report to group it. Standard reports read the five usual fields.

Related A/B testing terms

Related guide

Dynamic UTM tracking template: The tool page for building UTM templates. This glossary entry only defines the parameters.

FAQ

Which page should I use if I need a UTM generator or template?

The dynamic UTM tracking template. It is the page for filling in campaign, ad set, and creative values. This glossary page does not generate a URL and does not list ad-platform macros.

Do UTM parameters change what the visitor sees?

Not by themselves. They describe the click for analytics. A testing or personalization tool can read them and then change the page, but the parameter is only a label until something uses it.

What happens if two links use different spellings for the same source?

Analytics treats them as different sources. 'google' and 'Google' split one channel into two rows. The definition of each field has to be agreed once and reused, which is why teams keep a template instead of typing tags by hand.