Query String to JSON Converter
Parse URL query strings into structured JSON objects. Perfect for debugging API URLs and extracting parameters.
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Output
About Query String to JSON Converter
Debugging API requests and URLs often requires extracting query parameters into a structured format. Our Query String to JSON converter parses URL-encoded query strings and outputs clean, formatted JSON — making it easy to inspect parameters, modify values, and understand complex URLs. Whether you are debugging API requests in DevTools, analyzing tracking URLs from marketing campaigns, parsing server access logs, or reverse-engineering third-party integrations, this tool decodes and structures your query parameters instantly.
How to Use Query String to JSON Converter
Paste the Query String
Paste a URL query string into the input field. You can include or omit the leading ? character, and you can paste a full URL — the tool extracts the query portion automatically.
Review the Parsed JSON
The converter instantly decodes all percent-encoded characters and outputs clean, indented JSON with each query parameter as a key-value pair.
Copy or Download
Copy the structured JSON to your clipboard for use in code, config files, or API testing tools. Download as a .json file for further processing.
Common Use Cases
API Debugging
Extract and inspect query parameters from API request URLs to understand what data is being sent. Copy URLs from browser DevTools Network tab and parse them into readable JSON for quick debugging.
URL Analysis
Parse tracking URLs, analytics parameters (UTM codes), affiliate links, and deep links to understand their structure and verify correct parameter encoding.
Form Submission Debugging
Convert URL-encoded form data (application/x-www-form-urlencoded) back to JSON to inspect submitted field values, debug form handling issues, and verify POST body encoding.
Log Analysis
Parse query strings from server access logs, CDN logs, or application logs to analyze request patterns, popular parameters, and user behavior.
Marketing URL Analysis
Decode UTM parameters and tracking codes from marketing campaign URLs to verify correct tagging, analyze campaign structure, and audit analytics setup.
Third-Party Integration Debugging
When integrating with payment gateways, OAuth providers, or webhook services, parse their callback URLs to understand the parameters they send back to your application.
Why Use Our Query String to JSON Converter?
Instant Parsing - Paste any query string and get structured JSON immediately
URL Decoding - Automatically decodes percent-encoded characters back to readable text
Clean Output - Properly formatted JSON with 2-space indentation for easy reading and direct use in code
Full URL Support - Paste a complete URL and the tool extracts and parses only the query string portion
Privacy-First - All parsing happens client-side in your browser; URLs and parameters are never sent to any server
Developer-Friendly - Output is ready to use in JavaScript, Python, or any language that accepts JSON
Key Features
Parse URL-encoded query strings to clean JSON
Automatic URL decoding of all percent-encoded characters
Accepts full URLs or standalone query strings
Handles the leading ? character automatically
Clean, indented JSON output with 2-space formatting
Unicode and international character support
Copy result to clipboard instantly
File upload with drag and drop support
Download as .json file
100% client-side — no data leaves your browser
100% Client-Side Processing
Your data never leaves your browser
All processing happens in your browser using JavaScript. Your data is never sent to our servers or any third party. Safe for sensitive data, API keys, and production configs.
Frequently Asked Questions
Quick answers to common questions about query string to json converter
No. You can paste the query string with or without the leading ? character. Both "?name=Alice&age=28" and "name=Alice&age=28" work correctly.
Yes. Standard percent-encoded characters like %20 (space), %26 (&), and %3D (=) are automatically decoded to their original values.
If the same key appears multiple times, the last value wins. For array-like parameters, consider using a dedicated URL parser.
Yes. You can paste a complete URL like https://example.com/api?name=Alice&age=28 and the tool will extract and parse only the query string portion after the ? character.
Parameters using bracket notation like user[name]=Alice and user[age]=28 are parsed as flat key-value pairs (e.g., {"user[name]": "Alice", "user[age]": "28"}). The tool preserves the bracket syntax in the keys.
Yes. Query string parameters are inherently strings in the URL specification. The tool returns all values as JSON strings. If you need numeric or boolean types, you would cast them in your application code after parsing.
Yes. Copy the query string portion from any server log entry (Apache, Nginx, Cloudflare, etc.) and paste it into the tool. It handles both raw query strings and full URL formats.
Parameters with empty values like key= become {"key": ""} in the JSON output. Parameters without a value at all like key (no equals sign) are also handled and assigned an empty string value.
Yes! Use our JSON to Query String converter to go in the reverse direction. This is useful for modifying parameters and reconstructing the URL.
Learn More
Related JSON Tools
JSON to Query String
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Reverse — convert JSON back to URL query strings
JSON Formatter
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Further format and validate the parsed JSON output
JSONPath Query
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Query the parsed JSON with JSONPath expressions
JSON Tree Viewer
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Explore the parsed JSON as an interactive tree
JSON Diff
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Compare query parameters from two different URLs side by side