JSON to XML Converter

JSON and XML can both describe hierarchical data, but they disagree about several fundamentals. Converting between them is therefore a translation with judgment calls rather than a mechanical re-encoding, and knowing the sticking points helps you read the output critically.

XML has no arrays

This is the biggest structural gap. JSON marks a list explicitly with brackets, while XML expresses the same idea as a repeated element name and leaves the reader to infer that repetition means a collection. The consequence shows up on round trips: a list containing exactly one item converts to a single element. Converting back produces an object rather than a one-item array, because nothing in the XML distinguishes them. Wrapping collections in a container element is the usual defense.

Not every JSON key is a legal element name

XML names must begin with a letter or an underscore, cannot contain spaces, and cannot start with the letters xml in any capitalization, which is reserved. JSON keys have no such restrictions. A key that's purely numeric, contains a space, or starts with a digit therefore cannot be used directly as an element name. The converter has to escape or rewrite it. Any conversion of data with free-form keys deserves a look at what happened to them.

Types survive one direction only

JSON distinguishes the number 42 from the string containing 42, and the boolean true from the word true. XML content is text, and without an accompanying schema there's nothing marking which is which. Converting to XML therefore discards type information, and converting back has to guess. Empty values are similarly ambiguous. That's because a JSON null can become an empty element, a missing element, or an explicit nil attribute depending on the convention chosen, and these read back differently.

What XML still does better

XML remains the right choice in several contexts and it's worth knowing which, since conversion isn't always the goal. Schema languages allow a document to be validated against a contract before processing. XSLT transforms one document shape into another declaratively. Namespaces let vocabularies from different organizations coexist in one file without collisions. XML also supports mixed content, where text and markup interleave inside an element, which is how document formats represent a paragraph with emphasis inside it. JSON has no equivalent, so document-shaped data converts poorly in the other direction.