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Query Params to JSON

Convert URL query strings to JSON and back. Parse full URLs or ?key=value pairs, pretty-print, copy — 100% client-side.

Query Params ↔ JSON
Paste a URL, query string, or JSON — convert both ways, 100% in your browser

1 Query string / URL

2 JSON

3 Parsed parameters

KeyValue
Convert a query string or JSON to see parameters here
Supports key=value, key[]=a&key[]=b, key[0]=a, nested user[name]=Ada, and full URLs. Empty values and keys without = are kept.

What are URL query parameters?

Query parameters (also called query strings) are the key–value pairs that appear after the ? in a URL. For example:

https://example.com/search?q=hello+world&page=2&sort=date

Here q, page, and sort are parameters. APIs, search pages, filters, tracking links, and OAuth redirects all rely on them. Turning a query string into JSON makes it easy to inspect, edit, or feed into scripts and tests.

How to use this converter

  1. Paste a URL or query string

    Drop a full URL or just the part after ? into the left panel. Click “Convert to JSON” (or press Ctrl/Cmd+Enter).

  2. Inspect the JSON & table

    The right panel shows pretty-printed JSON. The table below lists every key and value with a copy button.

  3. Edit and convert back

    Change the JSON, then click “Convert to Query” to get a fresh query string. Toggle URL-encode as needed.

  4. Use sample data

    Click “Load sample” in the header to try a realistic URL with arrays and nested keys.

Key features

🔗
Full URL or raw query

Paste a complete URL or only the key=value part — both work.

📦
Arrays & nested keys

Supports tags[]=a, tags[0]=a, and user[name]=Ada.

🔄
Both directions

Query → JSON and JSON → query string with one click.

Pretty / minify

Format JSON for reading or minify it for pasting into code.

📋
Parameter table

Flat list of every key and value with per-row copy buttons.

🔒
100% client-side

Nothing is uploaded. Safe for tokens, internal IDs, and private URLs.

Common use cases

  • API debugging — Turn a long request URL into readable JSON to check filters, pagination, and IDs.
  • Building test fixtures — Convert sample query strings into objects for unit tests.
  • Tracking / UTM links — Inspect campaign parameters without guessing which keys are present.
  • OAuth & redirects — Parse callback URLs and state parameters quickly.
  • Editing in bulk — Pretty-print, change a few values, convert back to a query string.

Frequently asked questions

What does Query Params to JSON do?
It converts URL query strings (the part after ? in a URL) into a clean JSON object, and can convert JSON back into a query string. You can paste a full URL or just the key=value pairs.
Does it support arrays and nested keys?
Yes. It understands tags[]=js&tags[]=php, tags[0]=js, and nested forms like user[name]=Ada&user[role]=admin, and turns them into proper JSON arrays and objects.
Is my data uploaded to a server?
No. Everything runs in your browser with JavaScript. Query strings and JSON never leave your device.
Can I convert JSON back to a query string?
Yes. Paste JSON into the JSON panel and click “Convert to Query”. Nested objects become bracket notation; arrays become key[]=value pairs.
What about URL encoding?
You can toggle URL-decode when converting query → JSON, and URL-encode when converting JSON → query. Spaces can become + or %20 depending on the encoder.
Can I see a table of all parameters?
Yes. After conversion, the “Parsed parameters” table lists every key and value with a one-click copy button for each value.

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