This validator uses a strict YAML 1.2 parser and treats parser diagnostics as failures, including duplicate map keys and unresolved aliases. The preview is intentionally secondary: use it to inspect valid YAML, not as a replacement for a dedicated formatter.
Validador YAML
Funciona inteiramente no seu navegador - sem upload, sem cadastro.
Runs in your browser - nothing is uploaded.
YAML
Valid YAML preview
Paste YAML to validate it
Validador YAML
Funciona inteiramente no seu navegador - sem upload, sem cadastro. Funciona inteiramente no navegador. Sem upload, sem cadastro, grátis.
Como usar
- 1Paste YAML. Paste a YAML document or YAML stream into the input box.
- 2Read the status. The validator updates live and shows either Valid YAML or the first parser error.
- 3Use the location. When the parser exposes a position, jump to the reported line and column in your editor.
- 4Copy the preview. For valid YAML, copy the normalized preview or use the stats panel to review the document shape.
Para quem é
- Developers checking Kubernetes, GitHub Actions, Docker Compose, OpenAPI or app config before committing a change.
- DevOps and SRE teams catching indentation mistakes, duplicate keys and broken anchors before a deployment.
- Support engineers validating YAML snippets from tickets without uploading private environment values.
- Technical writers testing examples that include comments, lists, mappings and multiline block strings.
Perguntas frequentes
Is the YAML validator free?
Yes. The YAML validator is free to use, with no sign-up, no download and no usage limit. Paste YAML, read the validation result and copy the valid preview when you need it.
Is my YAML uploaded anywhere?
No. Validation happens locally in your browser. That is useful for deployment snippets, CI files, secrets templates and other configuration text you do not want to send to a server-side checker.
What errors can a YAML validator catch?
It can catch syntax problems such as broken indentation, missing colons, unterminated flow lists, duplicate map keys and aliases that reference a missing anchor. Parser wording can vary, but the status message shows the first diagnostic and location when available.
Does it validate multiple YAML documents?
Yes. YAML streams with document markers are parsed as multiple documents, and the stats panel reports the document count. If any document has a parser error, the whole input is marked invalid.
Is this also a YAML formatter?
It shows a normalized preview after validation, but the main job is syntax checking and diagnostics. Use the YAML formatter when you want indentation controls and a formatting-first workflow.
Why does valid-looking YAML fail?
YAML is whitespace-sensitive, so a single extra space can move a key into a different mapping or list. Strict parsers also reject duplicate keys and unresolved aliases because those cases make configuration files ambiguous or unusable.