Developer Utilities · Free tool
YAML / JSON / TOML Converter
Seamlessly convert between YAML, JSON, and TOML formats instantly. Paste any format to see the other two emit live — a free, private converter with no upload required.
Updated June 2026
Input format:
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What it does
Three-way data format converter. Paste in YAML, JSON, or TOML; the other two emit in real time. Uses yaml and @iarna/toml for parsing, both client-side so your config never leaves your browser.
For JSON-only formatting, see JSON Formatter. For converting between flat data formats, see JSON → CSV.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/yaml-json-toml-roundtrip" width="100%" height="720" frameborder="0" loading="lazy" title="YAML / JSON / TOML Converter" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Pick the input format.
- Paste your config (or use the sample).
- Read the other two formats side-by-side. Copy buttons on each.
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