Query String to JSON Converter
Developer
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.
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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