# Query String to JSON Converter

> Convert URL query strings to JSON and build query strings from JSON objects.

To convert a query string to JSON, paste a URL or the query portion and each parameter becomes a key. Repeated keys and bracket notation collapse into arrays, and percent-encoded values are decoded, so the JSON reflects what the server actually receives.

**URL:** https://convertto.tech/t/query-string-converter
**Category:** Data & Format Tools (https://convertto.tech/c/data-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Enter or paste your query string or json.
2. Choose the direction.
3. The result appears immediately — copy or download it.

## FAQ

### How are repeated parameters handled?

Inconsistently, across the web. ?tag=a&tag=b is an array in PHP and Rails, but only the last value in some frameworks. If you control both ends, an explicit array syntax removes the ambiguity.

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