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XML Validator
Syntax & Structure ValidatorReady
Paste or type data below, then click Validate Syntax (⌘↵) to check compliance.
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XML Validator & Syntax Checker

Validate XML syntax and tag closure online with real-time error reporting. Check well-formedness and detect unclosed elements directly in your browser.

Well-formedness check
Line/column errors
Attribute linting
Root element check
Step-by-Step Guide

How to Use XML Validator Online

Follow these quick steps to process your data online directly in your browser with zero latency and 100% privacy.

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Step 1Parses XML using the browser native DOMParser XML engine.
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Step 2Checks for well-formedness rules (single root, matching tag pairs, valid entity references).
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Step 3Reports syntax errors with exact line numbers.
Demonstration

Example Input & Output

Verifies that the XML document has a single root element, matching start/end tags, and valid attribute quoting.

XML Source
<?xml version="1.0" encoding="UTF-8"?>
<note>
  <to>Tove</to>
  <from>Jani</from>
  <heading>Reminder</heading>
  <body>Don't forget the meeting!</body>
</note>
Expected Output
✓ Valid XML (Well-Formed Document)
Applications

Common Use Cases

Pre-deployment Config Validation

Verify web.config, pom.xml, and AndroidManifest.xml before compilation.

RSS / Atom Feed Checks

Validate XML feed structures before publishing.

Guidelines

Specifications & Gotchas

Multiple Root Elements

XML documents must have exactly one root element.

Case Mismatch in Tags

XML is strictly case-sensitive; <Tag> and </tag> do not match.

Knowledge

Frequently Asked Questions

What is a well-formed XML document?

A well-formed XML document has matching opening/closing tags, proper nesting, attribute quotes, and a single root element.

How do I find XML syntax errors?

Paste your XML; the validator highlights the exact line and character where parsing failed.

Workflow

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