Assistools

XML Validator

Ensure your data is flawless with our advanced XML validator. Performs deep well-formedness checks and provides optional XSD schema support for structural verification, all processed 100% locally in your browser.

URL Parser / Query String SplitterBack to HomeJSON to XML Converter
Secure Connection: Your data is encrypted via SSL (HTTPS).
Privacy First: Processed in your browser. No data is stored or sent to servers.

How to use the XML Validator

Simply paste your content into the input area above. The tool will automatically process your data and show the result in the output box. All processing is done client side, meaning your data never leaves your computer.

What Is an XML Validator?

An XML Validator is a developer tool that checks whether your XML documents are well-formed and syntactically correct. It ensures that all tags are properly nested, closed, and follow XML syntax rules.

XML Validator - XSD (XML Schema)

This tool validates your XML string or file against specified XSD (XML Schema Definition) standards. The validator first checks for well-formedness, meaning that your XML file must be syntactically correct before it validates against the schema.

Why Validate XML?

XML validation is crucial for:

  • Data Integrity: Ensure your XML data is correctly structured before processing or transmission.
  • API Integration: Verify that API responses conform to expected formats.
  • Configuration Files: Validate config files before deployment to catch errors early.
  • Debug Errors: Quickly identify and locate syntax errors with line and column numbers.

Well-Formedness vs. Validity

Well-formed XML follows basic syntax rules: proper tag nesting, closing tags, and valid characters. Valid XML not only is well-formed but also conforms to a specific schema (XSD, DTD) that defines its structure and data types.

Encoding Support

Our validator supports multiple character encodings:

  • UTF-8: The most common encoding, supports all Unicode characters.
  • UTF-16: Used for documents with extended Unicode characters.
  • ISO-8859-1: Latin alphabet for Western European languages.
  • US-ASCII: Basic ASCII character set (128 characters).

Key Features

  • Well-Formedness Check: Verify XML syntax and structure.
  • XSD Schema Support: Optionally validate against XSD schemas.
  • File Upload: Load XML and XSD files directly from your device.
  • Detailed Error Reporting: Get line numbers and descriptions for any errors found.
  • Multiple Encodings: Support for UTF-8, UTF-16, ISO-8859, and more.
  • Privacy-First: All validation happens locally in your browser.