How are repeated keys handled?

When the same key appears more than once (for example tags=a&tags=b), it becomes a JSON array. A key that appears once stays a plain string.

Can I paste a full URL?

Yes. Everything up to and including the ? is ignored and any #fragment is dropped, so you can paste a complete URL and still get just the query parameters.

How are nested objects converted to a query string?

Arrays are expanded into repeated keys. A nested object or array of objects is serialized to JSON and percent-encoded as the value, since query strings are flat key-value pairs.

Is my data sent anywhere?

No. The conversion happens entirely in your browser; nothing is uploaded.

Query String to JSON Converter

Paste a query string (or a whole URL) and get a clean JSON object — repeated keys become arrays and values are percent-decoded. Switch direction to turn a JSON object back into an encoded query string. Perfect for inspecting API requests and building links. Everything runs locally in your browser — nothing is uploaded.

—

DirectionInput

Output

{
  "name": "Ada",
  "tags": [
    "dev",
    "math"
  ],
  "active": "true"
}

How to use

Choose the direction: query string to JSON, or JSON to query string.
Paste your query string (with or without the leading ?) or JSON object.
Copy the converted result from the output box.

Frequently asked questions

How are repeated keys handled?: When the same key appears more than once (for example tags=a&tags=b), it becomes a JSON array. A key that appears once stays a plain string.
Can I paste a full URL?: Yes. Everything up to and including the ? is ignored and any #fragment is dropped, so you can paste a complete URL and still get just the query parameters.
How are nested objects converted to a query string?: Arrays are expanded into repeated keys. A nested object or array of objects is serialized to JSON and percent-encoded as the value, since query strings are flat key-value pairs.
Is my data sent anywhere?: No. The conversion happens entirely in your browser; nothing is uploaded.

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