How do I convert YAML to JSON?

Paste your YAML into the source pane, leave the direction on YAML to JSON, and press Convert. The tool parses the YAML with a strict parser and emits pretty-printed JSON with your chosen 2 or 4 space indentation. If the YAML has a syntax problem the result pane stays empty and you get the exact line and column of the error instead.

Can it convert JSON back to YAML too?

Yes. Switch the direction to JSON to YAML (or just click Swap after a YAML to JSON conversion). It parses the JSON, validates it, and renders clean block-style YAML. You can toggle flow versus block style and disable YAML anchors and aliases if you want a fully expanded, copy-safe document.

Does it handle multi-document YAML?

Yes. A YAML stream with several documents separated by three dashes is loaded in full. When you convert to JSON, a single document becomes a JSON object or array and multiple documents become a JSON array of those documents, with a note telling you how many were merged.

What happens when my input is invalid?

Nothing is silently dropped. Invalid YAML shows the parser reason plus the offending line and column from the parser mark, and invalid JSON shows the parse position translated into a line and column. Both come with a short snippet of the surrounding lines and an arrow pointing at the failing line, so you can correct it without guessing.

Is my data sent anywhere?

No. The whole converter is JavaScript running in your browser. Your YAML and JSON never leave the page, there is no network request, and your last settings (direction, indent, sort keys) are stored only in this browser via local storage. It also works fully offline once the page has loaded.

Why would I sort the keys?

Sorting keys alphabetically gives you a deterministic output, which makes two configs easy to diff in version control and removes noise from reordered fields. The Sort keys option applies recursively to every object in the document, in both directions, while leaving array order untouched.

YAML to JSON Converter (Both Directions)

A bidirectional YAML and JSON converter that works either way: paste YAML and get clean JSON, or paste JSON and get readable YAML. It is built for developers wrangling Kubernetes manifests, CI pipeline files, Docker Compose configs, OpenAPI specs, Ansible playbooks and application settings — anywhere the same data has to live in both formats. Unlike a quick one-direction snippet, this tool validates the input first, reports errors with a real line and column, and lets you tune the output: indent width, recursive key sorting, block versus flow YAML style, and whether to expand YAML anchors. Everything runs locally, so even private credentials in a config file never leave your machine.

How it works

Under the hood the tool uses the battle-tested js-yaml parser. When you convert YAML to JSON, it loads the document with a strict schema, supports multi-document streams (the ones separated by ---), and serialises the result with JSON.stringify using your chosen indentation. When you convert JSON to YAML, it parses the JSON natively, then renders it back out with js-yaml using block style by default and an unlimited line width so long strings are not wrapped awkwardly.

Validation is the part most converters skip. If the YAML is malformed, the parser throws an exception carrying a mark with the failing line and column; the tool surfaces that plus a three-line snippet with an arrow at the bad line. If the JSON is malformed, the browser’s own parser reports a character position, which the tool converts into a line and column the same way. Either way you see exactly where the problem is instead of a vague “invalid input”.

The Auto-detect and convert button inspects the first non-blank characters of your source — a leading brace or bracket means JSON, otherwise it is treated as YAML — and flips the direction for you. Swap moves the result back into the source pane and reverses the direction, so a quick round-trip is one click. Results can be copied to the clipboard or downloaded as a .json or .yaml file, and your last-used settings persist in this browser.

Example

Paste this YAML:

name: gera-tools
replicas: 3
ports:
  - 80
  - 443

With the direction set to YAML to JSON and 2-space indent, you get:

{
  "name": "gera-tools",
  "replicas": 3,
  "ports": [
    80,
    443
  ]
}

Press Swap, then Convert, and the JSON round-trips straight back to the original block YAML. Now feed it broken YAML — say a list item indented one space too few — and instead of a result you will see something like YAML parse error: bad indentation of a mapping entry at line 4, column 3, with the surrounding lines shown so the fix is obvious. Toggle Sort keys and every object in the document is emitted in alphabetical order for clean version-control diffs.

Every conversion happens in your browser. No YAML, JSON, file contents or settings are ever uploaded, and the tool keeps working with your network disconnected.