JSON & YAML Linter — Online Formatter — desktop.engineer
Validate, lint and format JSON and YAML online with clean indentation and precise syntax errors.
Online JSON linter and YAML linter
Validate, lint and format JSON and YAML files directly in the browser. This online linter reports the exact line of syntax errors and outputs clean, properly indented code.
- JSON linter: paste your JSON, get validated, formatted output with 2-space indentation and a precise error location.
- YAML linter: powered by js-yaml, it detects indentation and syntax errors in YAML files (docker-compose, configuration, CI pipelines).
- Formatter: every valid document is normalized with consistent indentation, ready to copy.
A fast, free online linter for developers — nothing is uploaded, your data never leaves the browser.
FAQ
How do I validate JSON online?
Paste your JSON into the linter above: it reports the exact line and column of any syntax error and returns formatted output with consistent 2-space indentation.
How do I lint a YAML file?
Paste your YAML (docker-compose, CI pipeline, Kubernetes manifest): the linter detects indentation mistakes, tabs, duplicate keys and other syntax errors with precise locations.
Is my data uploaded to a server?
No — validation and formatting run 100% in your browser with js-yaml. Nothing is uploaded, nothing is stored.
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