Free tools/Paid media
UTM builder
Tag a link so analytics can tell you where the traffic came from, and get told when you are about to break it.
Runs in your browser. Nothing is sent anywhere, and nothing is stored.
How it works
A UTM is a set of query parameters on the end of your URL. Analytics reads them and files the visit under the source, medium and campaign you named.
Everything stays lowercase here on purpose. GA4 treats Facebook, facebook and FaceBook as three separate sources, and the fastest way to ruin a channel report is to let three people tag links three ways.
Source is where the traffic comes from, such as facebook, newsletter or a partner's name. Medium is the kind of traffic: cpc, email, social, referral. Campaign is the specific push. Term and content are optional, term for paid keywords and content to tell two versions of one ad apart.
The checks under the link catch what usually goes wrong: tagging an internal link, which restarts the session and overwrites the original source, and tagging a Google Ads destination, where auto-tagging already passes a gclid that manual UTMs can override.
Worked example
A Meta ad for a spring sale, pointed at a landing page and tagged source facebook, medium cpc, campaign spring-sale, content video-a, produces https://example.com/landing?utm_source=facebook&utm_medium=cpc&utm_campaign=spring-sale&utm_content=video-a
Common questions
Do UTM parameters hurt SEO?
Not if the page carries a self-referencing canonical tag, which tells Google the clean URL is the one to index. Without one, the tagged variants can be treated as separate pages.
Which parameters are required?
GA4 needs source and medium to attribute a visit properly. Campaign is required in practice if you ever want to compare one push against another. Term and content are optional.
Why does my tagged traffic still show as Direct?
Usually a redirect that strips query parameters, an in-app browser that drops them, or a typo in a parameter name. Test the link end to end and confirm the parameters survive to the final URL.
Should I use UTMs on Google Ads?
Use auto-tagging instead. It passes a gclid and reports more accurately, and manual UTMs layered on top can overwrite it and double-count. This builder warns you when the destination looks like a Google Ads link.
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