Parse a URL query string into JSON and build a query string from JSON, in your browser.
How to use the Query String
Choose a direction: query to JSON or JSON to query.
Paste a query string (with or without the leading ?) or a JSON object.
Copy the result, or swap to convert back.
Frequently asked questions
A key that appears more than once, like tag=a&tag=b, becomes an array in JSON, and arrays in JSON expand back into repeated parameters.
Yes. When converting to JSON, anything before the ? is ignored, so you can paste an entire URL.
Yes. Percent-encoded values are decoded when parsing and encoded again when building a query string.
A query string converter that turns URL parameters into a readable JSON object and back, handling repeated keys as arrays and decoding values.
It runs locally in your browser, so it is quick and your data stays private.
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