developer-tools
YAML Formatter
Format and validate YAML online for configs, CI files, front matter, and Kubernetes-style snippets with browser-local processing.
Tool workspace
The interactive tool requires JavaScript.
Instructions
2. Click "Format YAML" to normalize indentation, or "Validate YAML" to confirm that the parser accepts the document.
3. Review anchors, aliases, comments, secrets, and the target system schema before copying the result.
Paste YAML to normalize indentation, expand compact lists, and catch parser errors before copying a config snippet. The formatter runs in your browser, uses a YAML 1.2 parser, and does not execute YAML tags or code.
YAML Formatter parses the input first, then prints a two-space indented YAML result or a validation summary. It is useful for reviewing configs, front matter, and workflow files, but it does not verify application-specific schema, secrets, deployment safety, or vendor rules.
What the YAML Formatter checks
The tool parses YAML 1.2 locally, reports syntax errors, enforces unique mapping keys, and prints the document with two-space indentation. It catches common indentation, colon, quote, list marker, and bracket mistakes.
What it does not validate
The tool does not know whether a Docker Compose, GitHub Actions, Kubernetes, OpenAPI, or static-site config uses the right fields. It also does not check permissions, credentials, runtime behavior, or deployment safety.
Safe handling boundaries
YAML tags are parsed as data and no code is executed by the formatter. Browser-local processing avoids sending input to an API, but you should still avoid pasting production secrets or confidential customer data into pages you do not trust.