XML Validator
Validate XML documents online for free. Our XML validator checks for well-formedness errors, mismatched tags, duplicate attributes, invalid entity references, and XML specification compliance with detailed error messages and line numbers. Perfect for SOAP, RSS, SVG, pom.xml, Android layouts, and all XML documents.
Paste your XML content or upload a .xml file to check for well-formedness errors, mismatched tags, invalid attributes, entity references, and XML specification compliance.
Why Use Our XML Validator?
Instant Validation
Our tool to validate XML analyzes your content instantly in your browser. Validate XML files of any size with zero wait time — get detailed error reports with line numbers in milliseconds.
Secure & Private Processing
Your data never leaves your browser when you use our XML validator online tool. Everything is processed locally using JavaScript, ensuring complete privacy and security for sensitive configuration data.
No File Size Limits
Validate large XML files without restrictions. Our free XML Validator handles any size input — from small configs to massive files with thousands of entries.
100% Free Forever
Use our XML Validator completely free with no limitations. No signup required, no hidden fees, no premium tiers, no ads — just unlimited, free validation whenever you need it. The best free XML validator online available.
Common Use Cases for XML Validator
SOAP Web Service Payloads
Validate SOAP request and response XML payloads before sending to web services. Catch mismatched tags, missing namespace declarations, and malformed XML that would cause service invocation failures.
Maven and Build Configuration
Check pom.xml, build.xml (Ant), and other build configuration files for XML errors. Prevent build failures and dependency resolution issues caused by malformed XML configuration.
RSS and Atom Feed Validation
Validate RSS and Atom feed XML documents for well-formedness. Ensure your syndication feeds parse correctly in feed readers and aggregators by catching structural XML errors.
Android Layout and Manifest
Validate Android XML files including layout resources, AndroidManifest.xml, and string resources. Find tag nesting errors and attribute issues before building your Android app.
Enterprise Data Interchange
Validate XML documents used in B2B data exchange, EDI conversions, healthcare HL7/FHIR messages, and financial FIX/FpML transactions. Ensure well-formedness before processing.
SVG and XHTML Documents
Validate SVG vector graphics and XHTML documents for XML well-formedness. Catch unclosed tags, invalid entity references, and attribute errors that cause rendering issues in browsers.
Understanding XML Validation
What is XML Validation?
XML validation is the process of checking XML (Extensible Markup Language) document files (.xml) for syntax errors, structural issues, invalid values, duplicate keys, and specification compliance — helping you catch problems before deployment. XML is widely used for structured data exchange in web services (SOAP/REST), configuration files (Maven pom.xml, Spring beans, Android manifests), document formats (XHTML, SVG, MathML), and syndication feeds (RSS, Atom). Our free XML validator online tool checks your content instantly in your browser. Whether you need to validate XML for SOAP web services, RSS/Atom feeds, SVG graphics, Maven POM files, Android layouts, and data interchange between enterprise systems, our tool finds errors accurately and privately.
How Our XML validator Works
- Input Your XML Content: Paste your XML content directly into the text area or upload a
.xmlfile from your device. Our XML validator online tool accepts any XML input. - Instant Browser-Based Validation: Click the "Validate XML" button. Our tool analyzes your content entirely in your browser — no data is sent to any server, ensuring complete privacy.
- Review Detailed Error Reports: View a comprehensive list of errors with line numbers, descriptions, and severity levels. Fix issues with pinpoint accuracy using our clear error messages.
What Gets Validated
- Syntax Correctness: Checks for proper syntax including balanced brackets, correct string quoting, valid escape sequences, and proper key-value pair formatting.
- Data Types: Validates integers, floats, booleans, strings, datetimes, arrays, and inline tables conform to the XML specification.
- Structural Integrity: Detects duplicate keys, conflicting table definitions, invalid table headers, and malformed sections.
- Line-by-Line Reporting: Every error includes its exact line number and a clear description, making it easy to find and fix issues in your XML files.
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Frequently Asked Questions - XML validator
A XML validator is a tool that checks XML files for syntax errors, structural issues, invalid values, and specification compliance. Our XML validator online tool processes everything in your browser — giving you instant error reports with line numbers and clear descriptions.
Our XML validator detects syntax errors (missing brackets, incorrect quoting), structural issues (duplicate keys, conflicting table definitions), invalid data types (malformed numbers, dates, strings), invalid escape sequences, and specification violations. Each error includes its exact line number for easy debugging.
Absolutely! Your data is completely secure. All validation happens directly in your browser using JavaScript — no data is ever uploaded to any server. Your configuration files, secrets, and sensitive data never leave your device.
Yes, our XML validator is 100% free with absolutely no hidden costs or limitations. There's no signup required, no premium tier, no usage limits, no file size restrictions, and no advertisements. Use it unlimited times for any project.
Yes! Our XML validator online tool handles files of any size. Since all processing happens in your browser, performance depends on your device, but modern browsers handle even very large XML files efficiently.
Yes! Our XML validator checks that every opening tag has a matching closing tag with the exact same name. It reports the line and column of mismatched tags, making it easy to locate nesting errors in deeply nested XML documents.
Absolutely. The XML specification prohibits duplicate attribute names within the same element. Our validator detects duplicate attributes and reports them with the exact location and the element they appear in.
Yes! Our XML validator works with any XML-format file including SOAP envelopes, RSS/Atom feeds, SVG graphics, Maven pom.xml, Android layouts, Spring configuration, and any other well-formed XML document.