Web and product analytics
UTM parameters explained (with a free UTM builder)
The short answer
UTM parameters are tags added to a link (utm_source, utm_medium, utm_campaign, plus optional utm_term and utm_content) that tell analytics tools where a visit came from. Use them on every link you control outside your own site: email, social posts, partner links, QR codes. Never use them on internal links.
Key takeaways
- Source, medium and campaign are required; term and content are optional.
- Lowercase everything and keep mediums to a short list GA4 recognises.
- Never tag internal links, and let Google Ads auto-tagging handle ad clicks.
On this page 5 sections
The five parameters
| Parameter | Answers | Example |
|---|---|---|
| utm_source | Which site or sender? | newsletter, linkedin, partner-name |
| utm_medium | What kind of channel? | email, social, cpc, referral, qr |
| utm_campaign | Which campaign? | spring-sale-2026 |
| utm_term | Which paid keyword? (optional) | call-tracking-software |
| utm_content | Which link or creative? (optional) | header-button, video-ad-b |
Naming rules
- Lowercase everything. GA4 treats Email and email as different values.
- Use hyphens, not spaces.
- Keep medium values to a short fixed list that matches GA4's default channel rules (email, social, cpc, referral, display, affiliate), or your traffic lands in Unassigned.
- Write the conventions down and share them with everyone who builds links, including agencies.
Common mistakes
- UTMs on internal links: they restart the session and overwrite the real source.
- Tagging Google Ads links by hand when auto-tagging is on; let the GCLID do the work.
- Using utm_source for the campaign name, so every campaign looks like a new source.
- Sharing a tagged link on social, where others reshare it and credit flows to the wrong place. Use short links per channel.
Build links with the UTM builder. It runs entirely in your browser; nothing you type is sent anywhere.
Questions
- Do UTM parameters affect SEO?
- Not if pages set a canonical URL without the query string, as most sites do. Do not put UTM-tagged links on your own pages.
- Are UTM parameters case sensitive?
- Yes, in GA4 and most analytics tools. Keep everything lowercase.
Sources
Next step
Try the utm builder
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