Convert YAML to JSON Online — Free

How to convert YAML to JSON

1. 1

   Add your YAML file

   Drop or select a .yaml file. Files up to 50MB process locally in your browser — nothing uploaded.

2. 2

   Run the conversion

   Your YAML is parsed in the browser using js-yaml (YAML 1.2 compliant) and re-emitted as compact or pretty-printed JSON. Multi-doc YAML (--- separated) becomes an array of JSON objects. Anchors (&) and aliases (*) resolve during conversion.

3. 3

   Download your JSON

   One click saves the result as a .json file. Your original file stays on your device.

Why convert YAML to JSON?

Most APIs, JavaScript runtimes, and programmatic consumers expect JSON. Converting YAML to JSON lets you use DevOps configs written in YAML (Kubernetes manifests, GitHub Actions workflows, Ansible playbooks) in code that expects JSON — for validation, transformation, or inclusion in JavaScript frontends. JSON is also easier to feed into a REST API body than YAML.

Common YAML to JSON use cases

• Feeding a GitHub Actions workflow YAML into a script that validates it via JSON schema
• Converting a Kubernetes manifest from YAML to JSON for kubectl apply --validate=false or API-based deployment
• Translating Ansible inventory YAML into JSON for a custom orchestration tool or MCP server
• Importing a Docker Compose YAML into a JavaScript tool or Next.js build script that parses JSON

What file size to expect

A 2 KB Kubernetes deployment YAML becomes roughly 3-4 KB as JSON — 30-50% larger because JSON requires quotes around strings and keys, plus braces and commas for nesting. A complex Helm values.yaml of 15 KB produces a JSON of 20-25 KB.

Technical notes: YAML → JSON

YAML 1.2 parsing via js-yaml supports anchors (&name), aliases (*name), merge keys (<<), block and flow styles, and all standard tag mappings. Multi-doc streams (documents separated by ---) become a JSON array of objects. YAML's three null-equivalents (null, ~, empty) all become JSON null. Numeric strings in YAML 1.1 style ('yes/no/on/off' as booleans) are NOT interpreted as booleans — YAML 1.2 treats them as strings. Dates and timestamps in YAML can optionally convert to ISO 8601 strings; by default they stay as strings for JSON compatibility.

Compatibility and browser support

JSON output is RFC 8259 compliant — parseable by JSON.parse, Python's json.loads, Go's encoding/json, Java's Jackson, and every mainstream JSON library. Works in every browser for client-side use, in Node.js for server-side scripts, and in any programming language's standard library.

YAML vs JSON

Frequently Asked Questions