MediumMap is a free utm_medium generator and reference. Pick your channel groups, fix a naming style, and get a consistent set of medium values — each with a definition and a sample tagged URL. It exists because inconsistent medium values are one of the most common and most fixable causes of messy marketing reports.
What it is not
It is not analytics software and not attribution advice. Generated values are naming conventions; whether your tracking is correct depends on your implementation, which only your own testing can validate. The honest-limits box on the generator says as much.
How it is built
Static HTML, CSS and JavaScript. Randomization uses crypto.getRandomValues(), everything runs in your browser, no cookies, no tracking, no signup.