UTM tracking explained: what the parameters mean and how to use them

October 4, 2026 · 5 min read

You post a link on Reddit, put another in your newsletter, and a friend shares a third in a group chat. A day later your analytics shows a bump of "direct" traffic and you can't tell which one worked. UTM parameters fix that, and they take about a minute to learn.

What a UTM parameter is

A UTM parameter is a short tag added to the end of a link. When someone clicks, your analytics reads the tag and records where the visit came from. The name comes from "Urchin Tracking Module", an early analytics product, and the tags work in almost every analytics tool.

https://example.com/pricing?utm_source=reddit&utm_medium=social&utm_campaign=launch-week

The five parameters

• utm_source: where the link lives, such as reddit, newsletter or hacker-news.
• utm_medium: the kind of channel, such as social, email or cpc (paid clicks).
• utm_campaign: the specific effort, such as launch-week or october-newsletter.
• utm_term: the keyword, mainly for paid search.
• utm_content: which version of a link was clicked, useful when one email has two buttons.

Most people only ever need the first three. Add the other two when you are comparing variants.

A naming scheme that stays tidy

• Lowercase everything. Many tools treat Reddit and reddit as two different sources, and your numbers split in half.
• Use hyphens, not spaces. launch-week, not Launch Week.
• Keep a short list of mediums and reuse it: social, email, cpc, referral.
• One campaign name per thing you publish. Two Reddit posts under the same campaign can't be compared with each other.

Five mistakes that quietly ruin attribution

1. Tagging links inside your own site. In most tools an internal link with a UTM tag starts a new visit and overwrites the real source. Use UTMs only on links that point to your site from somewhere else.
2. Inconsistent spelling. twitter, x and Twitter are three sources unless you decide on one.
3. Forgetting to write down what you made. A month later nobody remembers what test2 was.
4. Reusing one campaign for everything. You get a total but no comparison.
5. Never checking the result. The point is the follow-up: which post brought visitors, and did they do anything?

Doing this without a spreadsheet

The usual way to keep UTM links organised is a spreadsheet nobody updates. In agentlytics you create the link on the Campaigns tab, or ask your coding agent to do it. The link is lowercased and tidied for you, and the campaign is logged so later traffic and signups are credited to it. You can then click the source on the dashboard to see only that traffic, or ask your agent "how did the Reddit post do?".

New to the setup? The Claude Code setup guide takes two minutes, and funnel analysis is the natural next step once you know where visitors come from.

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