UTM Parameters Explained: Read and Debug Tracking URLs
Learn what utm_source, utm_medium, utm_campaign, utm_content, and utm_term mean, then debug encoding, duplicate keys, fragments, and privacy problems.
In This Article
- Start With the Five Standard UTM Parameters
- Use Source for Where the Traffic Came From
- Use Medium for the Marketing Channel
- Use Campaign, Content, and Term for Detail
- Check Percent-Encoding Before Publishing
- Watch for Duplicate Keys and Fragments
- Do Not Put Personal Data or Secrets in UTM Tags
- Use a Pre-Publish Tracking-Link Checklist
Start With the Five Standard UTM Parameters
UTM parameters are query-string values added to a destination URL so analytics tools can classify campaign traffic. The common five are utm_source, utm_medium, utm_campaign, utm_content, and utm_term.
Paste a tracking link into the URL Parser to see each value separately. The parser reads the text locally and does not visit the destination.
Use Source for Where the Traffic Came From
utm_source identifies the specific platform, publication, partner, or list that sent the visit. Examples include google, linkedin, october_newsletter, or partner_name.
Choose stable names and document them. Switching between linkedin, linked-in, and LinkedIn creates separate reporting rows even though they describe the same source.
Use Medium for the Marketing Channel
utm_medium describes the broad channel, such as email, paid_social, organic_social, cpc, affiliate, or qr_code. Source and medium work together: newsletter/email is more informative than either value alone.
Do not put the campaign name into medium. That makes channel-level comparison unnecessarily difficult.
Use Campaign, Content, and Term for Detail
utm_campaign names the initiative, promotion, or launch. utm_content distinguishes creative variants, buttons, placements, or calls to action. utm_term was designed for paid-search keywords but can hold another documented targeting value when your reporting process requires it.
Use only the detail you will actually analyze. Empty or inconsistent tags add noise without improving attribution.
Check Percent-Encoding Before Publishing
Spaces, ampersands, plus signs, fragments, and nested URLs can change meaning when they are not encoded correctly. In a query string, an ampersand starts a new parameter, while percent-encoded %26 represents an ampersand inside a value.
Inspect the decoded table and confirm that campaign names and redirect URLs appear as one intended value rather than several accidental parameters.
Watch for Duplicate Keys and Fragments
A URL may contain the same key more than once. Some systems keep every value, while others use only the first or last. The URL Parser preserves repeats and groups them as arrays so the ambiguity stays visible.
Everything after # is the fragment. Browsers normally keep fragments client-side rather than sending them in the HTTP request, so UTM parameters placed after a fragment may never reach server-side analytics.
Do Not Put Personal Data or Secrets in UTM Tags
URLs can appear in browser history, analytics systems, logs, screenshots, referrer data, copied messages, and support tickets. Do not store email addresses, phone numbers, access tokens, customer IDs, or confidential notes in campaign parameters.
The parser masks common secret parameter names in copied JSON, but naming conventions cannot detect every sensitive value. Review the original link before sharing it.
Use a Pre-Publish Tracking-Link Checklist
Confirm that the destination loads, source and medium follow your naming convention, campaign is stable, optional content or term values are meaningful, and special characters decode correctly. Test the link in a private analytics property or staging campaign when possible.
Use UTM Builder to create consistent links, URL Parser to audit the finished address, and your analytics platform to confirm that the visit is attributed as expected.