XML Validator
Validate XML documents and catch malformed tags instantly.
ValidateLintClient-sideUnlimited
0 / 500,000
How to use
- Paste your XML. Drop any XML document.
- Read the verdict. Green pass or red fail with the offending node.
Common use cases
- Validating RSS feeds
- Debugging broken SVG files
- Checking SOAP envelopes
- Pre-flight checks on Android, iOS, and .NET resource files
Frequently asked questions
- What does this XML validator check?
- Well-formedness: matched tags, properly nested elements, single root element, escaped special characters, and valid attribute syntax. The validator reports the first error with its line and column.
- What is the difference between well-formed and valid XML?
- Well-formed XML follows the XML 1.0 syntax rules (matched tags, single root, escaped characters). Valid XML additionally conforms to a schema (DTD, XSD, or RelaxNG). This tool checks well-formedness only; for schema validation, use a dedicated XSD or RelaxNG validator.
- Are XML namespaces and CDATA sections supported?
- Yes. xmlns declarations, namespace prefixes, <![CDATA[…]]> sections, comments, and processing instructions are all parsed correctly. Malformed namespace usage is caught as an error.
- Does it validate against a DTD or XSD?
- No. This tool checks the XML 1.0 spec (well-formedness). Schema-based validation (DTD, XSD, RelaxNG) requires the schema document and a more complex validator.
- Does the XML get uploaded?
- No. Validation runs in your browser via fast-xml-parser; sensitive XML stays on your device.
Related tools
How to use
- Paste your XML. Drop any XML document.
- Read the verdict. Green pass or red fail with the offending node.
Common use cases
- Validating RSS feeds
- Debugging broken SVG files
- Checking SOAP envelopes
- Pre-flight checks on Android, iOS, and .NET resource files
Frequently asked questions
- What does this XML validator check?
- Well-formedness: matched tags, properly nested elements, single root element, escaped special characters, and valid attribute syntax. The validator reports the first error with its line and column.
- What is the difference between well-formed and valid XML?
- Well-formed XML follows the XML 1.0 syntax rules (matched tags, single root, escaped characters). Valid XML additionally conforms to a schema (DTD, XSD, or RelaxNG). This tool checks well-formedness only; for schema validation, use a dedicated XSD or RelaxNG validator.
- Are XML namespaces and CDATA sections supported?
- Yes. xmlns declarations, namespace prefixes, <![CDATA[…]]> sections, comments, and processing instructions are all parsed correctly. Malformed namespace usage is caught as an error.
- Does it validate against a DTD or XSD?
- No. This tool checks the XML 1.0 spec (well-formedness). Schema-based validation (DTD, XSD, RelaxNG) requires the schema document and a more complex validator.
- Does the XML get uploaded?
- No. Validation runs in your browser via fast-xml-parser; sensitive XML stays on your device.