Query String ↔ JSON

Convert URL query strings to JSON objects and JSON back to query strings, with repeated keys turned into arrays. Free online converter.

About this tool

Convert URL query strings to JSON and JSON back to query strings. Paste a full URL or just the part after ?.

tag=a&tag=b becomes "tag": ["a", "b"], and arrays become repeated keys in the other direction.

Yes. Percent-encoding and + for spaces are decoded.

Nested objects are written as JSON strings in the query value.

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