How to use
- Choose a conversion mode: JSON → YAML or YAML → JSON.
- Paste or type your JSON or YAML into the input box.
- The converted result appears automatically in the output box below.
- Click Copy to copy the formatted output to your clipboard.
Frequently asked questions
Is my JSON or YAML data uploaded to a server?
No. The conversion happens entirely in your browser using JavaScript. Nothing you paste ever leaves your device, so even sensitive config files and API keys stay private.
Can it convert in both directions?
Yes. Choose JSON → YAML to turn JSON into YAML, or YAML → JSON to parse YAML into formatted, indented JSON. Just switch the mode and the output updates instantly.
Why do I see an 'invalid input' message?
It means your input could not be parsed. Make sure JSON has quoted keys and no trailing commas, and that YAML uses consistent indentation with spaces (not tabs).
Does it support YAML comments and anchors?
Standard YAML structures parse correctly, but comments are dropped when converting to JSON because JSON has no comment syntax. Converting back to YAML will not restore removed comments.
Is there a size limit on the data I can convert?
There is no fixed limit. Because everything runs locally in your browser, conversion is only bounded by your device's memory — typical config files and API payloads convert instantly.
Is this JSON YAML converter free to use?
Yes, it is completely free with no sign-up, no watermarks, and no upload. You can convert JSON and YAML as many times as you like, entirely in your browser.
About this tool
Free online JSON to YAML and YAML to JSON converter that runs 100% in your browser. Paste your data, convert both ways instantly, copy the result — nothing is uploaded.