XML Validator - Check XML Syntax Online
Validate your XML documents instantly with our free online XML Validator. Check for well-formedness, syntax errors, and proper nesting to ensure your XML data is ready for processing.
Why Validate Your XML?
- Prevent Parsing Errors: Ensure XML parsers can read your data
- Data Integrity: Verify structure before processing or storage
- Interoperability: Ensure XML works across different systems
- Error Localization: Pinpoint exactly where issues occur
Common Use Cases
🔗 SOAP Web Services
Validate SOAP XML messages and payloads.
📄 RSS/Atom Feeds
Check XML feed validity before publishing.
🗄️ Data Exchange
Validate XML from external data sources.
⚙️ Config Files
Check XML configuration files (web.config, pom.xml).
How to Use This Tool
- Paste Your XML: Enter the XML document you want to validate.
- Click "Validate XML": Our parser checks your XML for errors.
- Review Results: Fix any issues shown and re-validate.
💡 Tip: This tool checks for well-formedness. For schema validation (XSD), you'll need additional tools.
XML Validator Tool
Results will appear here after validation...
XML Well-Formedness Rules
Valid XML must follow these rules:
- Single Root Element: Only one root element allowed
- Proper Nesting: Tags must be opened and closed in correct order
- Case Sensitive: <Tag> and <tag> are different elements
- Quoted Attributes: Attribute values must be in quotes
- Escaped Characters: <, >, & must be escaped in content
- Prolog Optional: <?xml?> declaration is optional but recommended
Common XML Errors
<tag></Tag>- Case mismatch in opening/closing tags<a><b></a></b>- Improper nesting<elem attr=value>- Unquoted attribute value<text>5 < 10</text>- Unescaped less-than sign
XML vs HTML
Unlike HTML, XML is strict about syntax. HTML browsers are forgiving with errors, but XML parsers will fail on any syntax violation. This strictness ensures data integrity but requires more careful authoring.
Related Tools
- XML to JSON Converter - Convert XML to JSON
- JSON to XML Converter - Convert JSON to XML
- HTML Validator - Validate HTML markup
- YAML Validator - Validate YAML data