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UTM Builder
Generate campaign URLs with consistent UTM parameters. Everything runs in your browser.
Values are lowercased and hyphenated automatically so your reports stay consistent.
What UTM parameters actually do
UTM parameters are plain query-string tags that analytics tools read to attribute a visit to a campaign. When someone clicks a tagged link, the landing URL carries the tags, and the analytics tool credits that session to the source, medium and campaign you specified instead of guessing from the referrer.
The three that matter for almost everyone: utm_source (where the link lives: newsletter, google, x), utm_medium (the channel type: email, cpc, social), and utm_campaign (which push: spring-launch, black-friday). utm_term and utm_content are for paid keywords and A/B-ing creatives; skip them unless you need them.
Naming conventions that save your reports
Tags are literal strings: "Newsletter", "newsletter" and "news-letter" become three different rows in every report. Pick a convention on day one: lowercase everything, use hyphens instead of spaces, and keep a shared list of allowed sources and mediums. This tool lowercases and hyphenates automatically so links built here are always consistent.
One more rule: never tag internal links. UTMs on links within your own site restart attribution mid-session and split one visit into two campaigns.
UTMs cover the links you control. For the traffic you do not tag, such as visits from ChatGPT, Perplexity and Claude, the referrer is all you get, and most tools misfile it. See how AI referral traffic reaches your site and how to attribute it without a tag.
Frequently asked questions
What is the difference between utm_source and utm_medium?
utm_source is the specific place the link was posted (google, newsletter, x). utm_medium is the type of channel (cpc, email, social). Together they answer 'where exactly' and 'what kind of channel'.
Do UTM parameters affect SEO?
Not when used properly on inbound campaign links. To avoid duplicate-content indexing of tagged URLs, your pages should carry a canonical tag, which nearly all frameworks and CMSs add by default.
Should I use UTM parameters on internal links?
No. Tagging internal links resets attribution mid-session, so one visitor shows up as two sessions from two campaigns. Use them only on links that bring people to your site from outside.
Are UTM parameters case-sensitive?
The values are, in every analytics tool: 'Email' and 'email' are counted as different mediums. Lowercase everything as a rule, which this builder does automatically.