developer-tools
Query String Parser
Parse URL query parameters locally in your browser, including key-value pairs, repeated keys, blank values, and grouped JSON.
Tool workspace
The interactive tool requires JavaScript.
Instructions
2. Click "Parse Query String" to review total parameters, unique keys, and repeated-key summary.
3. Check the grouped JSON; same-name parameters are preserved in order as arrays for debugging notes or scripts.
Paste a full URL, a query string that starts with ?, or a bare a=1&b=2 parameter fragment to inspect readable key-value rows. Processing stays in your browser and does not request the target URL.
The Query String Parser reads the part after ?, splits key-value pairs on &, decodes percent encoding and plus-as-space query syntax, and preserves repeated keys in order. Repeated keys are not overwritten; grouped JSON stores them as arrays.
What this parser is for
Use it to inspect callback URLs, UTM links, search parameters, API debugging URLs, and form submission results. The tool parses text only; it does not visit the target link or decide whether a URL is safe.
Repeated-key behavior
When the same key appears more than once, the detail table keeps every row and grouped JSON uses an array. For example, tag=json&tag=url keeps both values. Names such as __proto__, constructor, and toString are treated as ordinary own keys rather than inherited object properties.
Decoding boundaries
A + is decoded as a space and %2B as a literal plus. Lone % or incomplete hex sequences fail. Inputs with a URI scheme but no query, such as mailto:ops@example.com or urn:example:item, return no parameters instead of treating the whole URI as one key.