XML Formatter & Validator

XML Formatter & Validator parses and rebuilds any XML document in your browser using the native DOMParser API — no uploads, no server round-trips, no third-party libraries.

How it works

Paste your XML and click Format (or press Ctrl+Enter). The formatter passes the raw string to DOMParser with the application/xml MIME type, which triggers a strict parser built into every modern browser since 2010. If the document is well-formed, the formatter walks the DOM tree recursively, reconstructing the element hierarchy with consistent two-space indentation at every nesting level. Attributes are preserved in their original order; namespace declarations like xmlns and xmlns:prefix are carried through verbatim because the DOMParser makes them explicit in the attribute list.

If the document has an error, the formatter extracts the exact line number and column from the DOMParser's error output and translates cryptic browser messages into plain English — for example, “Attribute is missing a value” instead of the raw “Specification mandate value for attribute.”

Format vs. Minify

The Format mode re-indents the document for reading. The Minify mode strips all inter-element whitespace into a single line — the right choice when you need the smallest possible payload for an HTTP request body, a config diff, or a version-control snapshot where whitespace changes add noise.

What you can use it for

• SOAP APIs: Paste a SOAP response from curl or browser DevTools to inspect the element structure and spot unexpected nesting or missing namespaces.
• Maven and Ant builds: Format pom.xml or build.xml before committing to check for unclosed tags and verify namespace declarations.
• Spring configuration: Read Spring XML application context files with proper indentation — essential when auto-formatter settings vary across team IDEs.
• Atom and RSS feeds: Verify entry counts, link href values, and feed metadata structure without installing a feed reader.
• Request payloads: Minify XML before embedding it in an API request body or comparing it against a stored fixture.

What it does not do

The formatter checks that your XML is well-formed — correct tag nesting, valid attribute syntax, a single root element. It does not validate against an XSD schema. XML that passes here is structurally correct but not necessarily schema-valid.

There is no server-side file size limit because all processing runs locally in your browser tab. Very large documents (over 5 MB) may take a moment depending on your device.