Deep Dive: XML to JSON Converter
Converting XML to JSON involves parsing the XML into a DOM tree, then mapping elements to JSON objects. Attributes become properties prefixed with @ (by convention), child elements become nested objects, and repeated elements become arrays. XML namespaces (xmlns) get stripped or preserved depending on the parser. CDATA sections and mixed content (text + child elements) pose challenges—some parsers merge text nodes, others create separate properties. The conversion is lossy: XML's document order and attribute vs. element distinction disappear in JSON. Libraries like xml2js or fast-xml-parser handle this. Useful when integrating legacy SOAP APIs or RSS feeds with modern JavaScript.
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Privacy Architecture
This tool uses client-side WebAssembly to ensure your data never touches a server. Secure, fast, and 100% private by design.
Core Capabilities
- Convert XML to JSON via DOM parsing
- Handles attributes (prefixed with @) and nested elements
- Automatic syntax validation (catches unclosed tags)
- Pretty-print JSON output
- Syntax highlighting
- One-click copy
- Client-side DOMParser API
- Free tool, works offline
Why It Matters
- Modernization: Convert legacy XML data (SOAP, RSS, config files) to modern JSON.
- Integration: Easily use XML data in JavaScript applications (fetch APIs, React state).
- Readability: JSON is often easier to read and debug than verbose XML.
- Privacy: All processing happens in your browser (no server upload for sensitive data).
- Speed: Instant conversion for files of any size (limited by browser memory).
Quick Start Guide
Paste your XML code into the input editor.
The DOMParser parses it into an XML tree, then converts to JSON (attributes → @properties).
Check the JSON output in the right-hand panel.
Click 'Copy' or 'Download' to save your JSON data.
Use 'Clear' to reset the form.
Usage Examples
Basic XML to JSON
Scenario 01Convert simple XML structure
<person><name>John</name><age>30</age></person>
{"person": {"name": "John", "age": "30"}}XML with Attributes
Scenario 02Attributes become @ properties
<user id="123"><name>Jane</name></user>
{"user": {"@id": "123", "name": "Jane"}}Repeated Elements (Array)
Scenario 03Repeated tags become JSON arrays
<users><user>Alice</user><user>Bob</user></users>
{"users": {"user": ["Alice", "Bob"]}}Common Scenarios
Modernizing Legacy APIs
Convert old XML SOAP responses to JSON for modern apps.
RSS Feed Parsing
Read RSS/Atom feeds as JSON.
Configuration File Migration
Move from XML configs to JSON.
API Response Transformation
Work with XML APIs using JSON tooling.
Questions?
Technical Architecture
How XML→JSON Conversion Works
**The process**: 1. **Parse XML**: Build XML DOM tree from string 2. **Traverse Tree**: Walk through all elements recursively 3. **Map Elements**: Each tag becomes JSON key 4. **Handle Attributes**: Prefix with @ or similar convention 5. **Detect Arrays**: Repeated elements → JSON arrays 6. **Extract Values**: Text content becomes values **Example**: ```xml <person id='1'> <name>John</name> <email>john@example.com</email> </person> ``` Becomes: ```json { "person": { "@id": "1", "name": "John", "email": "john@example.com" } } ``` Element → object, attribute → @property, child elements → nested properties.
Attribute Handling Conventions
**The challenge**: XML has attributes AND element content: ```xml <user id='123'>John</user> ``` JSON can't represent this directly. **Common conventions**: **Option 1: @ prefix** (most common): ```json {"user": {"@id": "123", "#text": "John"}} ``` **Option 2: $ prefix**: ```json {"user": {"$id": "123", "_": "John"}} ``` **Option 3: Nested**: ```json {"user": {"attributes": {"id": "123"}, "content": "John"}} ``` Our tool uses @ convention (most widely adopted). Know which convention your API expects!
Array Detection in XML
**The problem**: XML doesn't have explicit arrays **XML example**: ```xml <users> <user>Alice</user> <user>Bob</user> </users> ``` **JSON result**: ```json { "users": { "user": ["Alice", "Bob"] } } ``` Repeated element names = array in JSON. **But what about single items?** ```xml <users> <user>Alice</user> </users> ``` Could be: - `{"users": {"user": "Alice"}}` (string) - `{"users": {"user": ["Alice"]}}` (array with one item) Depends on converter! Check output structure. Some always use arrays, some detect by count.
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