Convert YAML to JSON

Convert YAML to JSON in your browser: load your YAML, choose JSON as the target, and download the result. This conversion preserves every value in your data, and nothing is uploaded to a server.

Convert YAML to JSONRuns in your browser. Nothing uploaded.

When you need this

Almost every parser, schema validator and HTTP API speaks JSON. When a tool rejects your YAML — a CI step, a linter, an SDK that only accepts a JSON body — converting it is faster than arguing with the tool. It is also the way to find out what your YAML actually says, since anchors and merge keys are expanded in the output.

How to convert YAML to JSON

Load your YAML

Drag the .yaml or .yml file in from the repository you are working in. Indentation is preserved exactly as written, so a paste from a terminal works too. Nothing leaves your browser at this or any later step.

Choose the target format

Press Ctrl+Shift+K (Cmd+Shift+K on a Mac) to open the conversion panel, then pick JSON as the target. The source and the result sit side by side.

Read the loss report

The panel shows whether the conversion is lossless for your particular data, and lists every value it had to transform. Adjust indentation, key sorting and null handling if you need to.

Take the JSON

Download the .json file, copy it, or open it as a new tab to keep working on it in the JSON views.

What survives the conversion

YAML to JSON is lossless for your data: convert back and every value returns. Formatting does not survive — comments and whitespace are lost by every conversion in every direction, in every tool.

• Anchors and aliases are expanded to their values. &defaults / *defaults becomes the same content repeated at each use site: the data survives, the sharing does not, and the output can be noticeably larger than the input.
• Comments are dropped. JSON has no syntax for them, so any explanation of *why* a value is what it is exists only in the YAML.
• Duplicate keys in the source resolve to the last one seen, which is what the YAML spec requires but is worth knowing before you use the JSON as the source of truth.

A worked example

An anchor expanded at its use site:

defaults: &defaults
  retries: 3
staging:
  <<: *defaults
  host: stage.internal

{
  "defaults": {
    "retries": 3
  },
  "staging": {
    "retries": 3,
    "host": "stage.internal"
  }
}

Privacy

The conversion runs in your browser — in a Web Worker for anything above a quarter of a megabyte, so the page stays responsive. Your data is not uploaded, not logged and not stored. There is no account, and the whole thing works offline.

Convert YAML to JSON