YAML to TOML Converter

About this tool

Paste YAML and get TOML with the same data. The YAML is read with the safe JSON-compatible rules (so values such as yes, no and on stay text rather than becoming booleans), then written as TOML by the same writer as the JSON to TOML tool, which we verified against Python's tomllib. TOML has no null and needs a mapping at the top level, so YAML with null values or a list at the top gives a clear error, and you can tick Drop null values. Anchors and aliases are expanded; comments are dropped. Everything runs in your browser; nothing is uploaded.

How to use it

1. Paste your YAML.
2. Tick Drop null values if needed.
3. Copy the TOML.

Common problems

It says TOML cannot hold null

YAML values such as null, ~ or an empty value are null. Tick Drop null values or give them a value.

yes and no stay text

This tool reads YAML with the JSON-compatible core rules, where only true and false are booleans. Write true or false if you mean a boolean.

It says TOML needs an object at the top

A YAML list at the top level cannot be TOML. Put it under a key.