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How to use JSON to Query String

Paste a JSON object and the tool flattens it into an encoded query string, using bracket notation like items[0]=a for arrays and user[name]=x for nested objects.

Frequently asked questions

How are nested objects handled?

Keys are flattened with bracket notation, so { user: { id: 1 } } becomes user[id]=1, a convention many backends parse automatically.

How are arrays serialized?

Arrays use indexed brackets like tags[0]=a&tags[1]=b, preserving order when the query string is parsed back into a structure.

Are values encoded?

Yes — every key and value is percent-encoded so special characters remain valid within the resulting URL query string.

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