XML Validator
Validate XML syntax and structure instantly. Detect errors with precise line numbers and detailed messages. Free, secure, and runs entirely in your browser.
What is XML validation?
XML validation is the process of checking whether an XML document follows the rules of XML syntax, including proper tag nesting, correct attribute usage, and well-formed structure.
How does the XML validator work?
The validator uses the browser's built-in DOMParser to parse XML and detect syntax errors, providing detailed error messages with line and column numbers.
What types of XML errors can be detected?
The validator detects missing closing tags, mismatched tags, invalid characters, malformed attributes, incorrect nesting, and other syntax violations.
Is my XML data safe and private?
Yes, absolutely. All XML processing happens locally in your browser. Your data never leaves your device and is not sent to any server.
Can the validator check XML against a schema (XSD/DTD)?
This validator focuses on syntax and well-formedness checking. For schema validation (XSD/DTD), you would need additional specialized tools.
What is well-formed XML?
Well-formed XML means the document follows basic XML rules: every opening tag has a closing tag, tags are properly nested, and there is a single root element.
How to fix XML validation errors?
Review the error message which shows the exact line and column. Common fixes include closing unclosed tags, fixing typos in tag names, and ensuring proper nesting.
Does the validator support large XML files?
Yes, the validator can handle XML files of various sizes. Performance depends on your browser's capabilities and available memory.
Can I validate XML with namespaces?
Yes, the validator correctly handles XML documents with namespaces, checking both syntax and namespace declarations.
What are common XML syntax mistakes?
Common mistakes include unclosed tags, case-sensitive tag mismatches (XML is case-sensitive), missing quotes around attributes, and special characters not properly escaped.
Is this XML validator free to use?
Yes, this XML validator is completely free with no limitations. You can validate unlimited XML documents without registration.
Do I need to install any software?
No installation required. The validator runs entirely in your web browser and works on any device with a modern browser.
How to Use XML Validator
Validate XML syntax and structure instantly, with precise line numbers for every error. Everything runs locally in your browser.
- Paste your XML document into the editor area.
- Open the "Format" selector and pick "Original" to validate the text exactly as pasted.
- Choose "Prettify" or "Minify" to see how the document looks reformatted once it is valid.
- Read the error message and line number shown when validation fails, then fix that spot in your XML.
- Adjust the format option and re-check until the document is reported as well-formed.
The reported line number marks where the parser gave up, which is often after the actual mistake — check unclosed tags and quotes just above it.
Related Tools
- XML Beautifier Free online XML beautifier. Format, prettify and indent XML instantly in your browser with customizable options.
- XML to JSON Free online XML to JSON converter. Paste XML and get properly formatted JSON output instantly with validation and structure preservation.
- XML to YAML Convert XML to YAML format instantly. Paste XML and get clean, formatted YAML output with support for attributes, nested elements, and arrays.
- Chmod Calculator Free online chmod calculator to visualize and calculate Linux file permissions with checkboxes. Instantly convert between numeric (755, 644) and symbolic notation (rwxr-xr-x). Supports special permissions like setuid, setgid, sticky bit.
- ASCII Table Complete ASCII character encoding reference with decimal, hexadecimal, octal, binary codes, HTML entities, and character descriptions. Search and filter instantly.
- HTTP Request Tester Test REST APIs directly in your browser. Send GET, POST, PUT, DELETE requests with custom headers, body, and query parameters. View response status, headers, and JSON body instantly.
- .htaccess Generator Generate Apache .htaccess rules for redirects, rewrites, security headers, caching, compression, and more.
- Robots.txt Generator Free online robots.txt generator. Create and customize robots.txt files to control search engine crawling, manage crawler access, and optimize your site's SEO with an easy visual editor.