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URL Tool

Parse query parameters into JSON or build query strings from structured data.

URL Tool

Query String Parser Builder

Parse a query string into readable JSON or build a query string from a JSON object in the browser.

This is useful for debugging redirects, callback URLs, analytics parameters, and request payloads that travel in the query string.

Tool UI

Parse or build query strings

About the query string parser

This page converts URL query parameters into JSON and turns JSON objects back into query strings. It is built for developers working with redirects, callback URLs, tracking parameters, filters, and API requests.

Repeated keys are preserved as arrays in the parsed JSON output, which makes parameters like tag=json&tag=tools easier to inspect than they are in a raw URL.

How to use the query string tool

  1. Paste a raw query string and select Parse query to turn it into JSON.
  2. Or paste a JSON object and select Build query to generate URL parameters.
  3. Copy the result into your app, tests, redirect logic, or API request.

What is a query string?

A query string is the parameter section of a URL that appears after the question mark. It carries key-value pairs used for filters, identifiers, tracking tags, pagination, and many other web behaviors.

Why use a query string parser or builder?

Query strings become hard to read quickly, especially when values are encoded or repeated. A parser makes them readable, while a builder makes it easier to construct valid parameter strings from structured data.

Query string examples

A redirect URL might include parameters such as state, code, redirect_uri, and scope. Parsing those values into JSON makes it easier to spot a missing callback value, an unexpected scope, or a parameter that was encoded more than once.

For analytics links, this tool can separate values like utm_source, utm_medium, and utm_campaign so you can confirm a campaign URL before publishing it.

Parsing notes

  • The leading question mark is optional.
  • Repeated keys become arrays in the JSON output.
  • JSON object values are serialized as strings when building a query string.
  • Use the URL encoder tool when you need to encode a single value before adding it to a larger URL.