XML to JSON Converter

XML (Extensible Markup Language) and JSON (JavaScript Object Notation) are both structured data formats, but they use fundamentally different approaches to represent hierarchical data. XML uses nested tags with attributes, while JSON uses nested objects and arrays with key-value pairs. Converting between them requires resolving structural differences.



The converter uses the browser's built-in DOMParser API to parse XML into a Document Object Model (DOM) tree. It then traverses this tree recursively, converting each XML element into a JSON object property. Element names become JSON keys, text content becomes string values, and child elements become nested objects.



Several mapping decisions affect the output: XML attributes can be mapped to special keys (like "@name" or "_attributes"), text content mixed with child elements needs a designated key (like "#text" or "_text"), and repeated sibling elements with the same name are automatically grouped into JSON arrays. These conventions are necessary because JSON has no direct equivalent of XML attributes or mixed content.



The converter handles edge cases including CDATA sections, namespaces, self-closing tags, comments (which are typically stripped), and deeply nested structures. The output is formatted with proper indentation for readability. All parsing and conversion happen in your browser using JavaScript — your XML data is never sent to any server.

1. API Migration & Modernization
Organizations migrating from legacy SOAP/XML-based APIs to modern REST/JSON APIs need to convert XML response structures to JSON equivalents. Understanding the JSON representation of existing XML data helps developers design new API schemas that maintain data compatibility.



2. Data Integration Between Systems
When one system exports XML and another imports JSON, the converter bridges the format gap. Enterprise data feeds, partner integrations, and ETL (Extract, Transform, Load) pipelines frequently require XML-to-JSON transformation for downstream processing.



3. Frontend Development
JavaScript applications work natively with JSON but need extra parsing for XML. Converting XML configuration files, API responses, or data exports to JSON simplifies frontend data handling, eliminates XML parsing libraries, and enables direct use of JavaScript object notation.



4. Configuration File Conversion
Legacy applications using XML configuration files can be modernized to JSON. Converting .xml config to .json preserves the data structure while enabling use with modern tools, JSON schema validation, and JavaScript-based configuration loaders.



5. Data Analysis & Scripting
Data analysts working with XML data exports from databases, government data portals, or scientific instruments convert to JSON for processing with Python, JavaScript, or other languages that handle JSON more naturally than XML. JSON is also more compact, reducing storage and processing overhead.

• Understand attribute mapping conventions: XML attributes have no direct JSON equivalent. Common conventions prefix attribute keys with "@" or "_". Know how your target system expects attributes to be represented before converting.



• Watch for array detection: A single child element stays as an object property, but repeated elements with the same name become arrays. If your XML sometimes has one item and sometimes multiple, ensure the converter handles both cases consistently.



• Handle mixed content carefully: XML elements containing both text and child elements (mixed content) are complex to represent in JSON. The converter typically uses a "#text" key for the text portion, but this may not match your target schema expectations.



• Validate the output: After conversion, validate the JSON against your expected schema. XML's flexibility means the automatic conversion may not produce the exact JSON structure your application needs. Manual adjustments may be required.



• Strip unnecessary data: XML comments, processing instructions, and namespace declarations are often irrelevant in JSON context. Check that the converter removes these elements rather than including them as noise in the output.



• Consider data types: XML stores everything as strings. The converter may or may not automatically parse numeric values ("42" → 42) and booleans ("true" → true). Verify that data types in the output match your requirements.