YAML Formatter & YAML to JSON Converter

Format, beautify, and validate YAML online, convert YAML to JSON or JSON to YAML with accurate syntax verification, configurable indentation, and client-side privacy.

Interactive YAML Formatter & Bi-Directional Converter Workspace

Paste or edit raw YAML or JSON to beautify structure, validate indentation, convert formats, and copy or download results with zero server latency.

✓ YAML 1.2 Standards Compliant ✓ 2-Space & 4-Space Indentation ✓ Preserves Comments & Anchors ✓ 100% Client-Side In-Browser Execution

What Is YAML?

YAML (YAML Ain't Markup Language) is a human-readable data serialization language widely adopted across DevOps, cloud-native orchestration, and software development. Governed by the YAML 1.2 specification, YAML represents structural hierarchies using precise whitespace indentation rather than the curly braces and quotation marks mandated by JSON. YAML is the primary configuration format for Kubernetes manifests, Docker Compose services, GitHub Actions workflows, Ansible playbooks, and OpenAPI specifications.

How to Format and Validate YAML

  1. Paste or Edit YAML: Paste your raw YAML document, Kubernetes manifest, or Docker Compose configuration into the editor.
  2. Choose Indentation: Select your desired indentation level—2 Spaces (cloud standard) or 4 Spaces.
  3. Run Format & Beautify: Click Format & Beautify YAML to parse the document, validate syntax, standardize spacing, and preserve inline comments.
  4. Inspect Syntax Errors: If indentation is misaligned or illegal tab characters are detected, the validator reports the precise line and column location.
  5. Copy or Download: Use the one-click copy button or download the formatted .yaml file to commit into your repository.

YAML to JSON Conversion

Converting YAML to JSON maps YAML key-value dictionaries to JSON objects, YAML lists to JSON arrays, and resolves scalar datatypes according to RFC 8259 specifications. Anchors (&) and aliases (*) are expanded into concrete JSON properties. If your YAML stream contains multiple documents separated by ---, the converter wraps them into a root JSON array.

JSON to YAML Conversion

The reverse conversion transforms rigid JSON payloads into lightweight, indentation-based YAML. Nested objects become clean structural blocks without extraneous quotes, arrays are formatted as clean bulleted dashes (-), and quotes are applied only to strings containing colons, symbols, or reserved boolean keywords.

YAML Validation and Common Errors

  • Tab Characters: YAML strictly forbids tab characters for indentation. Always use spaces.
  • Inconsistent Indentation: Child keys must be indented further than parent keys. Mixing 2-space and 3-space indents breaks parsing.
  • Unquoted Special Characters: Strings containing colons followed by a space, hashes, or leading dashes must be enclosed in quotes.

Frequently Asked Questions (FAQ)

What is a YAML formatter?

A YAML formatter parses YAML documents, validates syntax according to YAML 1.2 specifications, aligns indentation consistently across all nested blocks, and removes unnecessary whitespace while preserving comments and anchors.

Are files uploaded to a server?

No. All parsing, validation, and conversion operations run 100% locally inside your web browser. Your configuration files and secrets are never transmitted or stored on remote servers.

Does YAML support comments?

Yes. Any text following a hash mark (#) is treated as a comment. When you format YAML with OwnFormatters, your comments are retained.

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