Developer

Query String Parser

Turn a query string into a readable table and JSON object, or build a correctly encoded query string from JSON.

Developer

Query string parser & builder

Local only

Query string or full URL

4parameters

Key	Decoded value
`utm_source`	newsletter
`utm_medium`	email
`tag`	pdf tools
`tag`	free

As JSON

{
  "utm_source": "newsletter",
  "utm_medium": "email",
  "tag": [
    "pdf tools",
    "free"
  ]
}

Nothing is uploaded

Parsing and building both use the browser's URLSearchParams on your device.

Query strings and encoding

A query string is a list of key/value pairs joined by &. Values must be percent-encoded, which is why a space becomes %20 and an ampersand inside a value becomes %26.

Repeated keys

A key can legitimately appear more than once. The table lists each occurrence; the JSON view groups repeated keys into an array so the structure stays lossless.

Good to know

Frequently asked questions

Can I paste a full URL?

Yes. Everything before the first question mark is ignored when parsing.

How are repeated keys handled?

They appear once per occurrence in the table and as an array in the JSON output.

Is my data uploaded?

No. Everything is parsed locally in your browser.

Does building escape special characters?

Yes. Values are percent-encoded automatically, so the result is always a valid query string.

Query string parser & builder

Query strings and encoding

Repeated keys

Frequently asked questions

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