YAML Validator Online — Validate & Format YAML

Validate YAML online and catch syntax errors instantly. Paste your YAML to check it, then format it cleanly — free, private, and with no signup.

Input
Output

How to use YAML Validator

  1. Paste your JSON into the editor, or upload / drag-and-drop a .json file.
  2. Use the toolbar to Format, Minify, or Fix your JSON.
  3. Switch to Tree, Graph, or Table to explore the structure.
  4. Filter values with a JSONPath query when you need a specific part.
  5. Click Copy or Download to save the result.

Features

Beautify & minify

One-click pretty-print or compact your JSON to a single line.

Validate & auto-fix

Catch syntax errors instantly and repair common mistakes automatically.

Tree, graph & table views

Explore nested JSON visually and edit it inline.

Transform tools

Stringify, unescape, parse nested JSON, and sort keys.

JSONPath filter

Query and extract exactly the values you need.

100% private

Everything runs in your browser — nothing is uploaded.

What is YAML Validator?

A YAML validator confirms that indentation, colons, and list syntax are correct so your configuration loads reliably. JSON Reader validates and re-formats your YAML locally, pointing out the exact problem when something is wrong.

Related JSON tools

Frequently Asked Questions

Everything you need to know about JSON Reader

Yes. Every JSON Reader tool is completely free with no signup and no usage limits.
Yes. All processing runs entirely in your browser — your JSON is never uploaded to a server.
Click Fix JSON. It automatically repairs common problems such as trailing commas, single quotes, unquoted keys, and missing brackets.
Yes. Switch to the Tree, Graph, or Table tabs to explore your JSON structure visually, then return to the Editor at any time.
You can upload or drag-and-drop JSON files up to 50 MB.