Protobuf to XML Converter

Example: Protobuf input and real XML output

The output below was generated by the same conversion code the converter uses, run on this sample when the page was built.

user {
  id: 42
  email: "dev@example.com"
  active: true
  roles: "admin"
  roles: "billing"
  profile {
    display_name: "Dev Ops"
    locale: "en-SE"
  }
}

<user>
  <id>42</id>
  <email>dev@example.com</email>
  <active>true</active>
  <roles>admin</roles>
  <roles>billing</roles>
  <profile>
    <display_name>Dev Ops</display_name>
    <locale>en-SE</locale>
  </profile>
</user>

XML output is 42% larger than the Protobuf input. The same data is 140 characters as minified JSON and 218 as pretty-printed JSON. Sizes are character counts, not tokens: token counts depend on the model's tokenizer (see the tokenizer comparison).

Protobuf to XML: what changes

• Reading Protobuf: Input is Protobuf text format (the readable form used in .textproto files and debug output), not the binary wire format. Repeated fields are collected into arrays; no .proto schema is read, so types are inferred from the values.
• Writing XML: XML needs exactly one root element. Several top-level keys, or a top-level key holding an array, produce sibling roots that are not well-formed XML, which is why this sample is wrapped in a single key. Keys prefixed with @_ become attributes.

Why Convert Protobuf to XML?

Use XML when working with legacy systems, SOAP APIs, or when you need rich metadata and validation schemas.