Query String Parser

The Query String Parser is a browser-based tool for turning URL query parameters into decoded, readable key-value data. In development, analytics, QA, and support work, you often need to inspect a long URL and answer practical questions such as which parameters are present, what percent-encoded values actually mean, whether repeated keys exist, and how the final parameter set would look once decoded.

This tool accepts either a full URL or just the raw query part, automatically extracts the text after the question mark, decodes percent-encoded values, treats plus signs as spaces, and groups duplicate keys into arrays. It offers both JSON and table view formats, so you can copy the parsed output as JSON or inspect key-value pairs individually at a glance.

It is useful for checking UTM parameters, debugging form submissions, verifying API request URLs, inspecting redirect chains, and reviewing campaign links before sharing them. If the query contains broken percent-encoding, the tool reports that as an error instead of silently producing misleading output. Everything runs locally in the browser, so URLs and parameter values stay on your machine.