YAML to JSON Converter

Paste YAML and get JSON — handy for tools and APIs that only speak JSON.

Quick presets

Indent

YAML

JSON

Handles nested maps and lists, inline [a, b] / {k: v}, quoted strings, comments, and block scalars (| keeps line breaks, > folds them). Anchors and tags aren't supported.

Runs in your browser — nothing you enter is uploaded or stored.

ToolFeather · Indent-aware

Scratchpad auto-saved

Stored in this browser (localStorage)

About the YAML to JSON Converter

Many tools and APIs accept only JSON, while your configuration or data might be written in the friendlier YAML format. This converter parses a common subset of YAML — nested maps defined by indentation, dash-prefixed lists, and scalar values — and produces clean, pretty-printed JSON.

Values are interpreted sensibly: true/false become booleans, plain digits become numbers, null and ~ become null, and quoted text stays a string. Indentation determines nesting, so keep it consistent (two spaces works well; tabs are converted to spaces automatically).

This is a lightweight parser, not a full YAML engine, so advanced features like anchors, multi-document streams, and block scalars aren't supported — but for everyday config it converts reliably, entirely within your browser.

Examples

name: app → { "name": "app" }

A dash list under ports: → a JSON array of numbers.

DEBUG: false → a real JSON boolean, not the string "false".

Frequently asked questions

4 answers

Which YAML features are supported?

Indentation-based maps, dash lists, and scalar strings, numbers, booleans and null. Anchors, aliases, multi-doc and block scalars are not parsed.

Do I have to use spaces for indentation?

Yes — YAML doesn't allow tabs for structure. This tool converts any tabs to two spaces to help, but consistent spacing gives the best result.

How are types decided?

Bare true/false become booleans, plain integers and decimals become numbers, null/~ become null, and quoted or other text stays a string.

Is my YAML uploaded?

No — parsing happens entirely in your browser.