TONL to XML Converter

Example: TONL 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.

#version 1.0
root:
  log:
    events[4]{latencyMs,level,service,ts}:
      42,info,auth,"2026-09-30T08:12:04Z"
      310,warn,billing,"2026-09-30T08:12:09Z"
      38,info,auth,"2026-09-30T08:12:15Z"
      1204,error,search,"2026-09-30T08:12:21Z"

<log>
  <events>
    <latencyMs>42</latencyMs>
    <level>info</level>
    <service>auth</service>
    <ts>2026-09-30T08:12:04Z</ts>
  </events>
  <events>
    <latencyMs>310</latencyMs>
    <level>warn</level>
    <service>billing</service>
    <ts>2026-09-30T08:12:09Z</ts>
  </events>
  <events>
    <latencyMs>38</latencyMs>
    <level>info</level>
    <service>auth</service>
    <ts>2026-09-30T08:12:15Z</ts>
  </events>
  <events>
    <latencyMs>1204</latencyMs>
    <level>error</level>
    <service>search</service>
    <ts>2026-09-30T08:12:21Z</ts>
  </events>
</log>

XML output is 136% larger than the TONL input. The same data is 337 characters as minified JSON and 572 as pretty-printed JSON. Sizes are character counts, not tokens: token counts depend on the model's tokenizer (see the tokenizer comparison).

TONL to XML: what changes

• Reading TONL: TONL documents start with a #version line and wrap the data in root. The TONL encoder writes object keys in alphabetical order, so the original key order is not kept.
• 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 TONL to XML?

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