YAML ↔ JSON
Convert YAML to JSON and JSON to YAML with clear error messages.
Runs entirely in your browser — nothing is uploaded.
About the YAML ↔ JSON
The Freemium.Tools YAML converter turns YAML into JSON and JSON into YAML in your browser, with clear messages when the syntax is wrong.
YAML is the configuration format for Kubernetes, GitHub Actions, Docker Compose and most CI systems, while APIs and JavaScript code want JSON. Converting between them is a daily task for anyone touching deployment config.
Indentation mistakes are the most common YAML problem, so the converter reports the exact line where parsing failed instead of a generic error.
How to use it
- 1Pick a direction. YAML to JSON, or JSON to YAML.
- 2Paste or drop the file. Works with .yaml, .yml and .json files.
- 3Copy or download. Save the converted file straight to your device.
Frequently asked questions
Why does my YAML fail to parse?
Almost always indentation: YAML requires spaces, never tabs, and every nested level must line up consistently. The error message names the failing line.
Are comments preserved?
No. JSON has no comment syntax, so YAML comments are lost when converting to JSON and cannot be restored on the way back.
Does it handle multi-document YAML?
Single documents convert cleanly. For files separated by ---, convert one document at a time.
Will long strings be wrapped?
Generated YAML wraps around 100 characters for readability, which is valid and parses identically.
Is my config uploaded?
No. Conversion runs locally, which matters because config files often contain internal hostnames.