XML Validator

Validate XML syntax and document structure with line and error location reporting.

Category: Developer

How to Use XML Validator

  1. Paste or type your input string, code snippet, or text block into the xml validator editor.
  2. Configure formatting rules, target case, indent spacing, or encoding parameters.
  3. Click Process to execute the transformation instantly inside browser memory.
  4. Copy the formatted output or download it as a text file.

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Frequently Asked Questions

What is the difference between well-formed XML and valid XML?

A 'well-formed' XML document adheres to fundamental XML syntax rules: exactly one root element, matching start/end tags, proper nesting, quoted attributes, and escaped entity characters. 'Valid' XML additionally conforms to a specific external DTD or XSD schema.

What are the most common XML validation errors detected by this tool?

The most frequent XML syntax errors include missing closing tags, mismatched tag casing (e.g., <Title> closed with </title>), unquoted attribute values, unescaped ampersands (& instead of &amp;), and missing root tags.

How does the tool report XML validation results?

When XML is valid, the validator outputs the root tag name, total direct child node count, and confirmation of well-formed syntax. If an error exists, it identifies the parser error text and approximate line location.

Can I validate SVG files and RSS/Atom feeds here?

Yes. SVG vector graphic files and RSS/Atom news feeds are standard XML documents. You can paste their markup into the validator to check that all tag hierarchies and namespaces are well-formed.

Are large XML files supported for browser validation?

Yes. Because validation runs natively inside your browser's DOM parser engine, it handles multi-megabyte XML documents smoothly without server upload limits.