Free XML Validator Online

XML still powers a surprising amount of the modern internet — RSS and Atom feeds, SVG graphics, SOAP web services, Android Manifest files, Maven and pom.xml build configurations, sitemap.xml files for search engines, OPDS catalogs, MathML, KML for Google Earth, plist files in iOS development, and config files for countless legacy systems. The trouble with XML is that even tiny syntax errors (a missing closing tag, an unescaped ampersand, an attribute without quotes) make the entire document unparseable, and the error messages from production parsers are often cryptic. Our free online XML validator catches these problems in milliseconds. Paste your XML — a feed, a SOAP envelope, an SVG, a config file, anything — and click Validate. The validator parses the XML using the browser's native DOMParser (the same parser used by Chrome, Firefox, Safari, and Edge to parse XML in production) and reports any well-formedness errors with the exact line and column where the problem occurs. Common errors it catches: missing closing tags (`<item>foo</itm>`), mismatched tags (`<item>foo</bar>`), unquoted attributes (`<item id=foo>`), unescaped special characters (`<item>A & B</item>` should be `A &amp; B`), invalid characters in element names (numeric prefix, spaces), wrong root element nesting, malformed entity references, and the classic UTF-8 BOM at the start of an XML declaration. Common workflows people run it for: debugging an RSS feed that breaks in feed readers, validating a sitemap.xml before submitting to Google Search Console, checking a SOAP request that the server rejects without explanation, verifying an SVG file that fails to render, validating an Android manifest before a build, and sanity-checking a hand-edited XML configuration before deploying. **Important boundary:** this tool checks well-formedness (syntax-level correctness) — it does NOT validate against an XSD schema or DTD (semantic-level correctness). Well-formedness covers 90% of real-world XML errors; for the remaining 10% (does this XML actually conform to the SOAP specification, the RSS 2.0 schema, the iCalendar format, etc.), use a schema-aware validator like xmllint, oXygen XML Editor, or your IDE's XML plugin. For most everyday debugging, well-formedness validation is exactly what you need. Everything runs in your browser using the native DOMParser API — your XML never travels to any server, never gets logged. Pair this with our [XML Formatter](/tools/xml-formatter) to beautify the validated XML, [JSON Formatter](/tools/json-formatter) for the JSON equivalent, [Sitemap Generator](/tools/sitemap-generator) for creating sitemaps from scratch, and [HTML Beautifier](/tools/html-beautifier) for HTML formatting.