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XML Validator

Validate XML syntax and structure.

Use the tool

Use XML Validator to check whether XML is well-formed before sending it to an API, parser, feed reader, sitemap tool, or integration partner.

Dev Workbench

XML Validator

Validate XML syntax and structure.

Input

Result

Run the tool to see output.
Lines: 0Chars: 0

Why use XML Validator

  • Validate XML payloads copied from APIs, SOAP responses, RSS feeds, or config files.
  • Find mismatched tags, missing closing elements, invalid characters, and entity issues.
  • Check XML before converting it to JSON, formatting it, or sharing it in a bug report.
  • Review sitemap, feed, and integration payload syntax before handoff.

About this tool

XML syntax validation

XML Validator checks whether a document is well-formed, including matching tags, proper nesting, valid entity references, and legal characters.

Useful before parser and integration work

Broken XML can fail API integrations, feed imports, sitemap processing, and configuration parsers. Validate the payload before debugging downstream code.

Validation versus schema compliance

Well-formed XML is only the first step. If a partner or system requires a specific DTD or XSD, also validate against that schema in the target workflow.

Example usage

Input

<note><to>Ada</to><body>Hello</body></note>

Output

Valid XML: root element note contains properly closed child elements.

Practical guide for XML Validator

Best practices

  • Validate XML before converting, importing, or sending it to an integration partner.
  • Escape ampersands and reserved characters in text and attribute values.
  • Use schema validation separately when a system requires a specific document model.

Common mistakes

  • Assuming formatted XML is valid XML.
  • Forgetting one root element around copied fragments.
  • Ignoring namespace and schema requirements after syntax passes.

How this tool works

  1. Step 1

    Open XML Validator and review the default example input.

  2. Step 2

    Paste your own input or upload source data when required.

  3. Step 3

    Run XML Validator to generate output instantly in the browser.

  4. Step 4

    Verify the output using the preview and formatting helpers on the page.

  5. Step 5

    Copy the final result and continue with a related tool if needed.

Use related links to continue your workflow and keep your output consistent across ToolHarbor pages.

JSON FormatterFormat JSON with readable indentation.JSON ValidatorValidate JSON input and return syntax status.XML FormatterFormat XML with consistent indentation.YAML ValidatorValidate YAML formatting rules.URL Slug ValidatorCheck if text is a valid URL slug.

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FAQ

What does XML Validator check?

It checks well-formed XML syntax such as matching tags, nested structure, entities, characters, and basic document shape.

Does this validate against XSD?

This page focuses on syntax and well-formedness. Use a schema-aware validator when you need XSD, DTD, or Relax NG compliance.

Why does valid-looking XML fail?

Common causes include mismatched tags, unescaped ampersands, invalid characters, namespace issues, and missing root elements.

Should I format XML before validating?

You can do either, but validation should be part of the final check before sending XML to another system.