UTM Link Builder

Problem

Tagging campaign URLs by hand is error-prone in small, specific ways — a missing utm_ prefix, an existing query param on the base URL getting clobbered instead of preserved, or utm_term/utm_content skipped because they feel optional until you're trying to tell two ad variants apart in a report three weeks later.

Approach

Built a small tool that does the mechanical part correctly every time: parse the base URL properly (so existing params survive), only add a utm_ param if the field actually has a value, and make copying the result a one-click action instead of a manual select-and-copy.

Key decisions

• Used the native URL/URLSearchParams parser instead of string-splicing the query string by hand — malformed URLs and existing params are exactly what hand-rolled string concatenation gets wrong.
• Term and content are visually separated from the three 'always fill these' fields, since those two are the ones that get skipped and then can't be recovered after a campaign has already run.
• No backend at all. A tool like this has no reason to touch a server, and it's one less thing that can be down when someone actually needs to tag a link fast.

Outcome

// TODO: No usage data yet — this is a self-initiated sample tool, not a deployed internal tool.