YAML Validator / YAML Formatter

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Options

Status
Idle
Documents

Drag & drop a YAML or JSON file here
Supported: .yaml, .yml, .json
Parsed structure will appear here.

What is a YAML Validator / YAML Formatter?

A YAML validator checks whether your YAML is syntactically valid and can be parsed correctly.

A YAML formatter makes YAML easier to read by applying consistent indentation and normalized structure.

How to use the YAML Validator / YAML Formatter

  1. Paste your YAML into the input field.
  2. Choose indentation size and optional key sorting.
  3. Click Format to pretty-print the YAML.
  4. Click Validate to only check syntax.
  5. Click Minify for compact YAML output.

Tips

  • YAML is sensitive to indentation, so even small spacing issues can break parsing.
  • Sorted keys can make configuration files easier to scan.
  • The parsed JSON preview is useful for checking how YAML is interpreted.
  • Use validation first if you only want to confirm syntax.

Related guides

Learn the workflow behind this tool and what to check next.

YAML checks before deploying configuration or data

Valid YAML can still produce unexpected values when parsers infer types, resolve aliases, merge mappings, or implement different specification versions.

Indentation and structure

Use spaces consistently and inspect nested mappings, sequences, multiline scalars, duplicate keys, and document separators.

Implicit types

Quote values that must remain strings, including dates, booleans, null-like words, numbers with leading zeros, and special notation.

Anchors and aliases

Review merges, reused nodes, alias expansion limits, and whether the destination parser supports the intended behavior.

Application validation

Validate against the expected schema and load with the same safe parser, version, and options used in production.

Privacy and usage

Built for quick checks without an account

Toolinix tools are designed for short developer tasks: paste a safe sample, inspect the result, copy what you need, and move on.

No login required

You can use the tools without creating an account, subscribing to a newsletter, or saving a workspace.

Local when possible

Formatters, generators, encoders, and text utilities generally run in your browser. Network diagnostics may need a server-assisted lookup to check public URLs, domains, or IPs.

Keep secrets out

Do not paste production passwords, private keys, access tokens, customer records, or regulated data into online tools unless your own security policy allows it.

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YAML Validator / YAML Formatter FAQ

Can this tool convert YAML to JSON?
Yes. It can parse YAML and show the equivalent JSON structure instantly.
Can it convert JSON back to YAML?
Yes. You can paste JSON and convert it into formatted YAML.
Does it support multi-document YAML?
Yes. It supports YAML documents separated by ---.
Is my YAML stored?
No. Everything runs directly in your browser.