Query String to JSON
Paste a query string, choose whether to infer numbers, booleans, and null, then create JSON locally without sending a request.
A leading ? is optional. + decodes as a space; use %2B for a literal plus.
A QUICK WALKTHROUGH
How to use this tool
- Paste a query string with or without a leading question mark.
- Choose type inference and pretty output options.
- Review and copy the JSON result.
URL query semantics
Parsing uses URLSearchParams. A plus sign represents a space and percent encoding is decoded. Empty values remain empty strings; repeated keys become arrays in encounter order.
Optional type inference
With inference enabled, exact true, false, null, and finite decimal strings become JSON values. Otherwise every decoded value remains a string.
GOOD TO KNOW
Common questions
What happens to repeated keys?
The first value is a scalar; a repeated key becomes an array containing all values in order.
Are plus signs decoded?
Yes. URLSearchParams treats + as a space in query strings; use %2B for a literal plus sign.
Does it send a request?
No. The string is parsed locally and never fetched.