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YAML Validator

Check a YAML document and show the first problem we find.

Straightforward YAML: maps, lists, and plain values. Tabs and multi-line blocks are rejected.

Status
Valid

Valid YAML.

Calculations happen in your browser.

Worked example

name: Ada, then a list under tags, is valid. A tab indent is rejected. A | block scalar is rejected, because multi-line text isn’t supported on this page.

FAQ

What YAML is accepted?
Maps, lists, quoted strings, numbers, true, false, and null, indented with spaces.
Why are tabs rejected?
YAML indent is defined in spaces. A tab is reported with a line number so you can replace it.
Does valid YAML here match every parser?
Not always. Anchors, tags, and multi-line blocks are intentionally unsupported, so a file can pass another parser and fail here.