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Query String to JSON

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Parse a URL query string into a JSON object

Parse a URL query string into a JSON object, with support for repeated keys, bracket-style arrays like `tag[]=a&tag[]=b`, and one level of nested object keys like `sort[by]=date`. Runs entirely in your browser.

JSON
{
  "q": "local tools",
  "page": "2",
  "tags": [
    "css",
    "json"
  ],
  "sort": {
    "by": "date",
    "dir": "desc"
  }
}

Everything on this page is processed in your browser. Nothing is uploaded.

What this tool does

A query string looks simple until it isn't: the same key can repeat, some APIs bracket array values, and others nest a whole object into a handful of bracketed keys. This tool decodes every key and value the way a browser would, then reconstructs the JSON shape those conventions imply, so you can read what a URL is actually going to send as parameters.

How to use it

  1. Paste a query string, with or without a leading '?', or load the example.
  2. Review the parsed JSON output.
  3. Copy the JSON result.

Privacy

This tool runs entirely in your browser. Your input is never uploaded, stored or shared — closing the tab removes it.

Frequently asked questions

Is my query string uploaded anywhere?
No. Parsing happens in JavaScript running in the page, so nothing you paste ever leaves your device.
How are repeated keys handled?
A key that appears more than once, with or without a `[]` suffix, becomes a JSON array of its values in the order they appeared.
Does it support nested objects?
Yes, one level: a key like `sort[by]=date` becomes `{"sort":{"by":"date"}}`, which covers the bracket convention most backend frameworks parse automatically.

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