XML Formatter

The XML Formatter cleans up Extensible Markup Language documents by re-indenting nested elements, aligning tags, and applying consistent spacing so that dense, machine-generated XML becomes readable to humans. It handles the three core operations developers reach for most: beautifying compact one-line XML into a properly indented tree, minifying verbose XML by stripping insignificant whitespace, and validating that the document is well-formed. Everything runs locally in the browser, so your data never leaves the page.

Beautifying works by parsing the document into a node tree and re-serializing it with predictable indentation for each nesting level, which makes it obvious where elements open and close and where attributes belong. Minifying does the reverse, collapsing line breaks and indentation that XML parsers ignore anyway, which shrinks payload size for SOAP requests, configuration files, RSS feeds, and API responses. The validator catches common breakages such as unclosed tags, mismatched element names, illegal characters, and missing root elements.

Typical use cases include debugging SOAP and XML-RPC payloads, tidying up Maven pom.xml or Android layout files, inspecting RSS and Atom feeds, reading sitemaps, and preparing XML fixtures for tests. It is also handy when an API returns minified XML that you need to scan by eye, or when you are diffing two documents and need them formatted identically first. Tools like a JSON Formatter or YAML Formatter cover the equivalent job for those data formats.

A practical note is that well-formed is not the same as valid against a schema, this tool checks structural correctness, not conformance to a DTD or XSD. When minifying, be careful with elements where whitespace is significant, such as those inside xml:space="preserve" or text-heavy content, since collapsing it can change meaning. For very large files, formatting in the browser is fast but memory-bound, so split enormous documents if the page slows down.