Query String Parser

What is Query String Parser?

Query String Parser deconstructs URL query strings into structured key-value pair tables and reconstructs them from individual parameters. It handles edge cases like repeated keys (array parameters), nested bracket notation used by PHP and Ruby frameworks, URL-encoded values, and empty parameters. The tool also supports editing individual parameters and instantly regenerating the full query string.

Marketing engineers debugging campaign tracking URLs, API developers composing request parameters, and full-stack developers parsing callback URLs from third-party integrations. The tool runs entirely in your browser — your data never leaves your device.

How to Use Query String Parser

1. Paste a full URL or just the query string portion (everything after the ? character)
2. View the parsed parameters displayed as a structured key-value table
3. Edit individual parameter values directly in the table and see the URL update in real time
4. Add new parameters using the input fields at the bottom of the table
5. Copy the reconstructed URL or just the query string portion to clipboard

Common Use Cases

• Debugging complex marketing UTM parameters by splitting tracking URLs into readable pairs
• Analyzing OAuth callback URLs to inspect state, code, and scope parameters
• Building filtered API request URLs by composing query parameters individually
• Decoding analytics URLs with deeply nested tracking parameters from ad platforms
• Verifying that form submissions serialize correctly into query string format

Pro Tips

• Parameters with the same key (like tags=js&tags=react) represent arrays — the parser correctly groups these into a single key with multiple values
• Watch for the # hash fragment — it is not part of the query string and is never sent to the server, so parameters after # are only accessible client-side
• URL-encoded spaces may appear as + (from form submissions) or %20 (from encodeURIComponent) — both are valid but mean different things depending on the encoding standard

Why Use This Tool?

• Privacy-first: All processing happens locally in your browser. No data is transmitted to any server.
• No installation required: Works in any modern browser on desktop or mobile.
• Completely free: No account, no credit card, no usage caps.
• Fast and reliable: Powered by modern Web APIs for near-instant results.

Related Concepts

Learn more about related topics: URLSearchParams API, application/x-www-form-urlencoded, URI fragment, RFC 3986.

Frequently Asked Questions