JSON to TOML Converter

This is a two-way converter between JSON and TOML. Pick a direction, paste your data, and copy the result. It is built on a well-tested TOML parser that handles nested tables and arrays of tables correctly.

Everything runs locally in your browser, so your data, which for config files can include hostnames or tokens, never leaves your device.

TOML (Tom's Obvious, Minimal Language) is a configuration format designed to be obvious to read and to map cleanly onto a hash table. It is what Rust's Cargo uses for Cargo.toml and what Python projects use for pyproject.toml, among many others.

JSON and TOML describe similar data but suit different jobs. JSON is the lingua franca for APIs and machine exchange. TOML is built for human-written config, with sections, comments and first-class dates that make a settings file pleasant to edit.

TOML also supports native date and time values and typed numbers, so values keep their meaning rather than all becoming strings, which is part of why it is preferred for configuration.

Most data round-trips cleanly, but there is one catch. TOML has no null value. JSON nulls cannot be represented, so remove or replace them before converting to TOML, otherwise the conversion cannot express them.