How are nested objects encoded?

Bracket notation: `user[name]=alice&user[age]=30`. Alternative styles (dot notation, JSON-encoded values) are toggleable.

Three modes: repeated key (`tag=a&tag=b`), bracket with index (`tag[0]=a&tag[1]=b`), or comma-separated (`tag=a,b`). Default matches standard URL encoding.

Are values URL-encoded?

Yes — automatically percent-encoded. Spaces become `%20` (default) or `+` (form mode).

Does the output start with `?`?

Toggle — include the leading `?` for appending to a base URL, or omit it when the context already has one.

JSON → Query String | DevTools Surf

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Example: JSON → Query String

A worked example, rendered from real sample data. Sign in to run the tool on your own input.

Input

{"page":1,"limit":20,"tags":["admin","editor"],"active":true,"q":"hello world"}

Output

?page=1&limit=20&tags=admin&tags=editor&active=true&q=hello+world

Parameters: 6
URL encoded: %3Fpage%3D1%26limit%3D20%26tags%3Dadmin%26tags%3Deditor%26active%3Dtrue%26q%3Dhello%2Bworld

Examples:
https://example.com?page=1&limit=20&tags=admin&tags=editor&active=true&q=hello+world
curl 'https://example.com?page=1&limit=20&tags=admin&tags=editor&active=true&q=hello+world'

About JSON → Query String

JSON → Query String preview - Converters tool

Serialize a flat JSON object into a URL query string. Part of the DevTools Surf developer suite. Browse more tools in the Converters collection.

Use Cases

API developers converting JSON payloads to GET request params
Frontend devs serializing filter state into shareable URLs
Test automation engineers building parameterized test URLs
Backend devs migrating POST body parameters to query strings

Tips

Paste a flat JSON object to instantly get a query string
Nested objects are not supported — flatten them first
Output is URL-encoded and ready for direct use in requests

Fun Facts

JSON was formalized by Douglas Crockford in 2001 and standardized as ECMA-404 in 2013, despite being based on a subset of JavaScript syntax from 1999.
The application/x-www-form-urlencoded MIME type used for query strings is the default encoding for HTML forms and dates back to HTML 2.0 (RFC 1866, 1995).
The qs npm library, which handles nested JSON-to-query-string conversion, receives over 60 million weekly downloads — one of npm's most depended-upon packages.

FAQ

How are nested objects encoded?: Bracket notation: `user[name]=alice&user[age]=30`. Alternative styles (dot notation, JSON-encoded values) are toggleable.
What about arrays?: Three modes: repeated key (`tag=a&tag=b`), bracket with index (`tag[0]=a&tag[1]=b`), or comma-separated (`tag=a,b`). Default matches standard URL encoding.
Are values URL-encoded?: Yes — automatically percent-encoded. Spaces become `%20` (default) or `+` (form mode).
Does the output start with `?`?: Toggle — include the leading `?` for appending to a base URL, or omit it when the context already has one.

Related Converters Tools

JSON to XML JSON to CSV JSON to YAML JSON to TSV JSON to String XML to JSON XML to CSV XML to String