freesabaiYAML to JSON converter
Paste YAML and get JSON at once. If the YAML is wrong you are told the line and the reason. It handles comments, anchors (&), aliases (*), multi-line text and files with several documents. It runs in your browser and your YAML is not sent anywhere.
This tool needs JavaScript. If you still see this after a few seconds, JavaScript is switched off in your browser or the page did not load completely: turn JavaScript on or reload the page.
How to use it
- Paste YAML in the left box, or open a .yaml / .yml file. The JSON appears on the right.
- Choose the JSON indent, or "Minify".
- Press "Copy", or "Download" a .json file.
Frequently asked questions
Where is my YAML wrong?
The tool gives the line and column where the YAML reader stumbled. The usual causes are indentation that does not line up, tabs instead of spaces (YAML does not allow tabs to indent), a missing space after :, or a repeated key in the same mapping.
What do yes, no and dates become?
By YAML 1.2, yes and no are text, not true and false, and a date like 2026-10-10 is text. This tool reads it that way. If you want a boolean, write true or false.
What happens to YAML with several documents (separated by ---)?
You get a JSON list (array) of all the documents in order, and the tool tells you so.
Good to know
- Anchors and aliases are expanded into repeated values, because JSON has no references.
.infand.nando not exist in JSON, so they becomenull.- A whole number longer than 15 digits is read as a floating-point number and its last digits may be rounded. Put it in quotes to keep every digit.
- Comments in YAML do not exist in JSON, so they are dropped.
Your data stays on your device
Everything runs in your browser. What you type, paste or open is not sent to freesabai's servers or anyone else's, and is not kept in the browser: close the page and it is gone. The site only counts how many times this page was opened and how many times someone copied or saved a result (never what was pasted or the result, and you can switch the counting off in the footer; see the privacy policy).
Report a problem or suggest an idea
Found a bug, or want this tool to do more? Tell us on the feedback page. No sign-up.
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