Online XML/JSON Converter: Convert Between Data Formats

What Are XML and JSON

XML (eXtensible Markup Language) is a markup language for marking data, supporting attributes and namespaces.

JSON (JavaScript Object Notation) is a lightweight data exchange format using key-value pairs.

Comparison Example

XML:

<user id="1">
  <name>Alice</name>
  <email>alice@example.com</email>
  <tags>
    <tag>developer</tag>
    <tag>admin</tag>
  </tags>
</user>

JSON:

{
  "user": {
    "@id": "1",
    "name": "Alice",
    "email": "alice@example.com",
    "tags": {
      "tag": ["developer", "admin"]
    }
  }
}

XML vs JSON Comparison

| Feature | XML | JSON | |---------|-----|------| | Readability | Medium | High | | File size | Large (tag redundancy) | Small | | Data types | ❌ All strings | ✅ Multiple types | | Attribute support | ✅ Native | ⚠️ Convention-based | | Namespace | ✅ Supported | ❌ Not supported | | Comments | ✅ Supported | ❌ Not supported | | Schema validation | ✅ XSD | ✅ JSON Schema | | Web standard | Legacy | Modern |

Why You Need XML/JSON Conversion

1. Web service migration: SOAP (XML) → REST (JSON) API upgrade
2. Config file conversion: Legacy XML config → modern JSON config
3. Data integration: Different systems use different formats
4. RSS/Atom parsing: RSS Feed (XML) → JSON processing
5. Office documents: .docx/.xlsx are XML-based, need JSON conversion
6. Legacy system integration: New systems connecting to XML-based old systems

Common Conversion Challenges

| Challenge | Description | Solution | |-----------|-------------|----------| | Attributes vs elements | XML attributes have no standard JSON representation | Use @attr prefix | | Repeated elements | XML allows repeated element names | JSON converts to array | | Text content | XML mixed content | Use #text key | | Namespaces | XML namespace prefixes | Use full URI in JSON | | Empty elements | <tag/> | Use null or empty string in JSON |

How to Use an Online Tool

Using ToolVault's XML/JSON Converter:

1. Paste XML or JSON data
2. The tool auto-detects format and converts
3. Handles attributes, namespaces, and complex structures
4. Real-time preview of conversion
5. Supports streaming for large files

Conversion in Code

JavaScript

const { XMLBuilder, XMLParser } = require('fast-xml-parser');

// XML → JSON
const parser = new XMLParser({ ignoreAttributes: false, attributeNamePrefix: '@_' });
const xml = '<user id="1"><name>Alice</name></user>';
const json = parser.parse(xml);

// JSON → XML
const builder = new XMLBuilder({ ignoreAttributes: false });
const xmlStr = builder.build(json);

Python

import xmltodict
import json

# XML → JSON
xml_str = '<user id="1"><name>Alice</name></user>'
data = xmltodict.parse(xml_str)
json_str = json.dumps(data, indent=2)

# JSON → XML
data = {"user": {"name": "Alice"}}
xml_str = xmltodict.unparse(data, pretty=True)

FAQ

How to Convert XML Attributes to JSON?

No standard conversion exists. Common conventions: use @ prefix for attributes (e.g., @id), use #text for text content. Different tools may use different conventions.

Does JSON to XML Lose Information?

Possibly. JSON features unsupported by XML: arrays (require element name conventions), types (XML is all strings). Understand target format limitations before converting.

When to Use XML vs JSON?

Use XML for: namespaces, strict Schema validation, mixed document content (e.g., XHTML). Use JSON for: Web APIs, config files, frontend-backend data exchange. Modern projects prefer JSON.

This article is brought to you by ToolVault. More developer tools at the homepage.