JSON to Query String

Convert flat JSON to a URL query string and back. Supports common array conventions: tags[]=a&tags[]=b (PHP), tags=a&tags=b (Rails/many), tags=a,b (CSV).

How to use the JSON to Query String

Pick direction. JSON→Query handles arrays via the chosen convention; Query→JSON auto-detects which convention the source uses (groups repeats into arrays, parses foo[] and foo[0] notation).

Converting JSON and query strings

A URL query string and a flat JSON object carry the same kind of data, but moving between them by hand means wrestling with percent-encoding and, worst of all, arrays — because there is no single agreed way to encode them. PHP expects tags[]=a&tags[]=b, Rails and many others repeat the key as tags=a&tags=b, and some APIs want a comma-joined tags=a,b.

This converts flat JSON to a query string and back, with the array convention selectable and percent-encoding handled per RFC 3986. Going the other way it auto-detects which convention the source used. For converting JSON into a hierarchical wire format instead of a query string, the JSON to XML converter handles nested structures.

Common use cases

  • Build a request URL — turn a params object into a query string.
  • Parse a URL — convert a query string back into a JSON object.
  • Match a framework — choose the array style PHP, Rails, or your API expects.
  • Encode safely — get correct RFC 3986 percent-encoding.
  • Debug params — read a messy query string as structured JSON.

Frequently asked questions

Which array conventions are supported?

Bracket style (tags[]=a), repeated key (tags=a&tags=b), and comma-joined (tags=a,b).

Does it auto-detect the style when parsing?

Yes — converting a query string to JSON detects which convention the source uses, including bracket and indexed notation.

Is the encoding standards-compliant?

Yes — percent-encoding follows RFC 3986.

What about nested objects?

Query strings are flat by nature; to convert nested JSON to a hierarchical format use the JSON to XML converter.
Embed this tool on your site

Free to embed, no attribution required (but appreciated). Paste this where you want the tool to appear: