What Is XML Formatter & Validator?

A free online XML formatter and validator. Beautify XML with proper indentation, minify for production, and validate syntax with clear error messages including line numbers. View statistics on elements, attributes, and file size. All processing is local.

XML is a widely used format for configuration files, API responses, data interchange, and document storage. Working with raw XML can be difficult — missing indentation, inconsistent formatting, and hard-to-find syntax errors make manual reading and editing error-prone. XML Formatter & Validator provides three core functions in a single tool: format, minify, and validate.

Format mode takes raw, compact, or poorly indented XML and applies proper hierarchical indentation. Each nested level receives consistent indentation, making the document structure immediately visible. Elements, attributes, and text content are clearly separated. This is essential for debugging XML-based configuration files, reviewing API payloads, and preparing XML for documentation.

Minify mode does the opposite: it removes all unnecessary whitespace, newlines, and indentation to produce the most compact XML representation possible. This is useful for reducing file size in production deployments, preparing data for bandwidth-constrained transmission, or generating compact storage formats. The minified output is functionally identical to the original.

Validate mode parses the XML using the browser's built-in DOMParser and reports any syntax errors with precise line numbers and descriptions. Common errors caught include unclosed tags, mismatched tag names, invalid attribute syntax, and improperly nested elements. The statistics panel shows the element count, attribute count, and file size for both the input and output, giving you quantitative insight into your XML document's structure.