Query String to JSON

Query String to JSON takes the part of a URL after the question mark and turns it into a readable JSON object you can inspect, copy or paste into code.

Query strings are compact and URL-encoded, which makes them awkward to read by eye; this tool decodes every key and value, expands percent-encoding, converts the "+" shorthand back into spaces, and lays everything out as formatted JSON.

It is smart about the messy cases.

You can paste a bare query string, a string with a leading question mark, or an entire URL — the tool finds the query portion automatically and ignores any "#fragment" at the end.

When the same key appears more than once, as it often does for checkbox groups or multi-select filters, the repeated values are collected into an array rather than silently overwriting each other.

A key with no value becomes an empty string, so nothing is lost.

Because the whole conversion runs locally in your browser, the URLs you paste are never uploaded or logged, making it safe for links that contain tokens, session ids or other sensitive parameters.

It also keeps working offline once the page has loaded, so it is a handy companion when you are debugging API requests or analytics links.