JSON to Query String Converter NZ

This tool converts between a JSON object and a URL query string, the encoded key-value text that carries parameters in a web address. A query string is the part of a URL after the question mark, a series of key-value pairs joined by ampersands, such as the parameters that drive a search or filter a page. Web applications constantly need to move between this flat string form and the structured objects their code works with: building a query string from an object to make a request, or parsing one back into an object to read the parameters. Doing it by hand means fiddly percent-encoding and splitting, which is exactly where mistakes creep in. This converter handles both directions. You paste a JSON object and it builds the corresponding query string, properly URL-encoding each key and value so spaces and special characters are safe, or you paste a query string and it parses it back into a formatted JSON object. The result updates as you type and runs entirely in your browser. Use it to build request parameters, to read and debug a query string, to convert between the two forms, or for web development. When converting JSON to a query string, each property becomes a key-value pair, with values encoded so that spaces become percent-twenty and other special characters are escaped, keeping the URL valid. When converting back, the pairs are split, decoded and assembled into a JSON object. The tool works best with flat objects of simple values, which is what query strings naturally represent; deeply nested objects and arrays can be encoded in several competing conventions, so for those a dedicated library matching your framework is safer. For the common case of a flat set of parameters, this gives you a correct, ready-to-use result instantly in either direction.

Advertise on this page

JSON object or query string

Direction

Result

name=Calculate&page=2&q=tax%20tools

Best for flat objects of simple values. Encodes/decodes each key and value. Nested objects and arrays have competing conventions; use a framework library for those. Runs in your browser.

How it works

To build a query string, each property of the JSON object becomes a key-value pair, with the key and value URL-encoded so spaces and special characters are safe, joined by ampersands. To parse a query string, it is split on ampersands and equals signs, each part is decoded, and the pairs are assembled into a JSON object.

Worked example

The JSON object with name Calculate, page 2 and q tax tools becomes the query string name=Calculate&page=2&q=tax%20tools, with the space in the search term encoded as percent-twenty. Switching to the other mode and pasting that query string back rebuilds the original JSON object.

Related calculators

URL Encode/Decode: percent encoding.
JSON Formatter: format JSON.
YAML to JSON: YAML conversion.
Base64 Encoder: encode data.

Frequently asked questions

What is a query string?

It is the part of a URL after the question mark: a set of key-value pairs joined by ampersands, such as name=Calculate&page=2. It carries parameters that drive searches, filters and other behaviour. Values are percent-encoded so special characters stay valid in the URL.

How do I build a query string from JSON?

Each property of the object becomes a key-value pair, with the key and value URL-encoded and the pairs joined by ampersands. This tool does it for you, encoding spaces and special characters so the resulting query string is valid in a URL.

Does it handle nested objects and arrays?

It works best with flat objects of simple values, which is what query strings naturally represent. Nested objects and arrays can be encoded in several competing conventions, so for those a library matching your web framework is the safer choice.