JSON to YAML Converter — Free Online JSON→YAML Tool

Paste any JSON and get clean, readable YAML in seconds. Runs 100% in your browser with the open-source js-yaml library (MIT) — no upload, no sign-up. Supports nested objects, arrays, strings, numbers, booleans and null, with automatic indentation and comment preservation. Live preview, one-click copy, .yaml download, and the input is remembered in your browser. Perfect for developers writing config files, Docker Compose, Kubernetes YAML, CI/CD pipelines, Ansible playbooks and API configs — private, free, instant.

JSON input Anchor

YAML output

Converted YAML will appear here…

How to use

Paste or type your JSON into the left box — a sample is already loaded on first visit.
The right side updates live as you type (debounced ~250 ms).
Use Copy YAML to copy the result to your clipboard, or Download .yaml to save it locally.
The left input is remembered in your browser, so you can come back and keep editing.

What is it

JSON describes data with curly braces, square brackets and quotes; YAML describes it with indentation and colons. YAML removes all the braces and quotes, relying on indentation to show hierarchy, making it more concise and human-friendly. This tool parses your JSON with the built-in JSON.parse and serializes it into neatly indented YAML using the open-source js-yaml library, so you can paste the result straight into Kubernetes, Docker Compose or CI/CD config files.

Notes & fun facts

YAML is a human-friendly data serialization format proposed in 2001. Its name is a recursive backronym deliberately emphasizing that it is not a markup language, but designed for humans to read and write. YAML uses indentation instead of curly braces, colons instead of key-value separators, and dashes instead of array symbols, removing all the repetitive punctuation of JSON. Today YAML is practically the de facto standard for cloud-native configuration: Docker Compose files are YAML, Kubernetes Deployments and Services are YAML, GitHub Actions pipelines are YAML, Ansible playbooks are YAML, and CircleCI and GitLab CI are YAML. When you need to turn a JSON config into YAML for a CI/CD pipeline, or generate a Kubernetes manifest from API JSON, you need a fast, local, server-free tool. This tool does it locally in your browser with js-yaml, supporting nested objects, arrays, multi-line strings and comment preservation, ready to paste straight into your config files.

Origin & history

YAML 1.0 was proposed by Clark Evans in 2001, YAML 1.1 was released in 2005, and YAML 1.2 in 2009 aligned with JSON syntax. js-yaml is an MIT-licensed YAML parser/serializer open-sourced in 2011, zero-dependency and browser-friendly, and one of the most popular YAML libraries in the Node.js ecosystem. With the rise of cloud-native and DevOps, YAML has largely replaced JSON and XML in the config file domain.