I built a CLI to catch broken UTM parameters before they wreck your analytics

One mistyped utm_medium — Email instead of email — splits one
marketing channel into two rows in every dashboard downstream. It's a
tiny bug that's easy to miss when you're pasting links by hand into
Google Ads, Mailchimp, or a social scheduler.

I built urldn-utm-validator to catch it before the link goes out.

Install

npx urldn-utm-validator "https://yoursite.com?utm_source=fb&utm_medium=cpc&utm_campaign=q3"

What it catches

• Missing required params (utm_source, utm_medium, utm_campaign)
• Duplicate keys in the query string
• Inconsistent casing (Facebook vs facebook — these count as two separate channels in most analytics tools)
• Unencoded spaces
• Non-standard utm_medium values, as a soft nudge

It scores the URL 0-100 and prints plain-English fixes instead of just
flagging the problem.

Node API

import { validateUtm } from "urldn-utm-validator";

const result = validateUtm(
  "https://example.com?utm_source=fb&utm_medium=cpc&utm_campaign=q3"
);

console.log(result.score);   // 100
console.log(result.valid);   // true
console.log(result.issues);  // []

Also works with --json for CI pipelines, and --strict if you want
warnings to fail the build too, not just hard errors.

Repo: https://github.com/urldn/urldn-utm-validator
npm: https://www.npmjs.com/package/urldn-utm-validator

I maintain this alongside URLdn,
a link shortener with an AI layer that reads your click data directly
and answers questions about it in plain English — this validator is
the free standalone piece of that same problem.