UTM Parameter Audit
Check a set of tagged URLs for inconsistent casing, missing parameters and tagged internal links.
About this tool
Reads a list of tagged URLs and finds the inconsistencies that quietly split an analytics report in two.
**UTM values are case-sensitive.** `Facebook`, `facebook` and `FaceBook` are three separate sources in every platform, and a report that should be one line becomes three, each with a share of the traffic and none of them obviously wrong. Nobody notices until somebody asks why social is down.
**A tagged internal link is worse than a mistake.** Google Analytics starts a new session whenever it sees a campaign parameter, so a UTM-tagged link from one page of your site to another ends the visit and starts a fresh one attributed to the campaign. The real source is lost and the campaign is credited with a conversion it did not cause.
Also checked: reserved medium values that corrupt a standard channel, parameters that were misspelled and are therefore ignored, and campaigns missing a source or medium — which analytics needs before it can group anything.
Common questions
Does capitalisation really matter?
Yes, in every platform. Facebook and facebook are two different sources, and a report showing both looks like a data problem rather than a tagging one. Lower case throughout is the only convention that avoids it.
Why should I not tag internal links?
Because a campaign parameter starts a new session. The visitor arrived from search, clicked an internal link you tagged, and is now attributed to the campaign — with the original source gone and the conversion credited to the wrong thing.
Which parameters are required?
Source and medium. Without both, analytics cannot place the traffic in a channel and it usually lands in "unassigned". Campaign is strongly advisable; term and content are optional.
Should I avoid utm_medium=referral?
Yes. Analytics assigns referral itself for untagged traffic from other sites. Setting it manually mixes your tagged traffic in with that and makes both unreadable.