EZ Formatter

YAML Formatter

Format, validate, and convert YAML documents with syntax highlighting and error detection

Runs locally

YAML Input

Formatted Output

Inspector

Paste valid YAML — structure, tree and key paths appear here automatically

Advanced Options

Compare with another YAML

Send this document to Data Diff and paste a second version to see what changed.

Validation with the exact error position

Validation runs on every keystroke using the js-yaml 1.2 parser. Valid documents get live counts of documents, mappings, sequences, keys and depth. Broken ones report the exact line and column, a probable cause, and a highlight at the failing position — not just \"syntax error\".

Common YAML errors this tool pinpoints

These mistakes account for most invalid YAML. Each one is detected with a position and a probable cause:

Bad indentation

A child line indented less than its parent, or siblings that do not align. Usually reported as \"bad indentation of a mapping entry\" at the exact line.

TAB character

YAML forbids tabs in indentation. The parser reports \"found a tab character that violates indentation\" and highlights the offending line.

Duplicate key

The same key twice in one mapping. js-yaml reports \"duplicated mapping key\" with the line of the second occurrence.

Missing colon or space

A key without a value (\"key key2\") or a colon glued to the key (\"key:value\" is a plain string, not a pair). Reported as \"could not find expected ':'\".

Before / After

Minified Kubernetes manifest on the left, the same document formatted with 2-space indent on the right. Structure, tree and paths update from the parsed document.

Before (flow style)
{apiVersion: apps/v1, kind: Deployment, metadata: {name: web-app}, spec: {replicas: 3, template: {metadata: {labels: {app: web}}}}}
After (block style)
apiVersion: apps/v1
kind: Deployment
metadata:
  name: web-app
spec:
  replicas: 3
  template:
    metadata:
      labels:
        app: web

YAML quick reference (YAML 1.2)

  • Indentation is structure: spaces only — TAB characters are never allowed for indentation.
  • A colon must be followed by a space to be a key separator: \"key: value\", not \"key:value\".
  • Scalars resolve to types by the core schema: true/false (booleans), integers, floats, null (~ / null / empty). Note \"yes\"/\"no\" are plain strings in 1.2.
  • Multiple documents in one file are separated by a \"---\" line; \"...\" ends a document.
  • Anchors (&base) and aliases (*base) keep files DRY; merge keys (\"<<: *base\") inherit mappings.

Next steps with this data

Formatting is the first step. Continue the workflow without leaving your browser:

Compare with another YAML

Data Diff

 JSON Inspector

Inspect the converted JSON

 JSON → CSV

Export converted data to spreadsheet

Yaml Formatter Formatting for Australian Developer Workflows

In Australia, Yaml Formatter files drive APIs at Sydney fintechs, media pipelines in Melbourne, mining-tech in Perth, and coursework at Go8 universities like UNSW and Melbourne. Aussie teams typically follow Yaml Formatter conventions aligned with APAC practice: 2-space indent for JS stacks, AEST/AEDT (Australia/Sydney) timestamps, AUD dollar amounts, and dd/mm/yyyy dates in business payloads. Our formatter handles Yaml Formatter the way Australian engineers actually work — no registration, no upload, your data never leaves your device, which matters under the Privacy Act 1988 and Australian Privacy Principles. Whether you're cleaning an API response in Barangaroo, validating config for a Brisbane agency, or prepping data for a thesis in Adelaide, everything runs client-side and finishes in milliseconds — handy on NBN connections and mobile data alike.

Frequently Asked Questions

Common questions about Yaml Formatter formatting answered

Yes. All Yaml Formatter processing happens locally in your browser, with no upload to any server. This no-upload design aligns well with the Privacy Act 1988 and the Australian Privacy Principles for handling personal information.

The formatter preserves your original timestamps unchanged and works seamlessly with Australia/Sydney (AEST/AEDT), Australia/Melbourne, Australia/Brisbane, Australia/Perth and Australia/Adelaide timezones. Date values are not altered.

Absolutely. No registration, no login, no SSO needed. Just open the page and format your Yaml Formatter immediately, with no usage telemetry tied to your identity — convenient for enterprise and government environments.

The formatter follows the YAML 1.2 specification, ensuring compatibility with modern tools like Kubernetes, Docker Compose, GitHub Actions, and other cloud-native platforms.

Yes, the bidirectional conversion feature lets you convert YAML to JSON and JSON to YAML while preserving data types, nested structures, and comments where applicable.

Absolutely. The formatter is designed to handle Kubernetes manifests, Docker Compose files, CI/CD pipelines, and other multi-document YAML files with proper section separation.

The validator checks indentation consistency, proper use of colons and dashes, quoted string balance, anchor and alias references, and provides line-specific error messages for quick debugging.

Yes, the formatter correctly handles YAML anchors (&), aliases (*), and merge keys (<<), preserving these DRY features while formatting the surrounding structure.

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