YAML Tools
YAML Linter
Lint YAML for syntax errors, duplicate keys, and style issues.
Loading tool…
What is YAML Lint?
A YAML linter that combines js-yaml syntax validation with style checks developers actually hit: tabs in indentation, trailing whitespace, and duplicate keys.
How it works
The document is parsed with js-yaml (which rejects duplicate keys), then each line is scanned for tab indentation and trailing whitespace.
- Enter your input. Type or paste your input into the field above — the tool responds instantly.
- Review the result. Output updates live as you type. Everything runs entirely in your browser.
- Copy or download. Use the Copy button to grab the result, or Download to save it as a file.
Examples
Realistic sample
Paste or type any realistic input — the tool computes the result locally and instantly.
Common mistakes
Expecting a server round-trip
Nothing is uploaded — every tool in this category runs entirely in your browser.