YAML to JSON Converter
Convert YAML to JSON in your browser. Nothing uploaded.
Built with js-yaml (MIT), self-hosted.
How to use this tool
- Paste YAML.
- Convert.
- Download JSON.
Convert YAML to JSON in your browser. Nothing uploaded.
How it works
This tool converts YAML (YAML Ain't Markup Language) text into equivalent JSON, running entirely in your browser without uploading anything.
YAML is a human-friendly data format common in configuration files (Docker Compose, Kubernetes manifests, CI/CD pipelines, etc.). JSON is more universally accepted by APIs and programming libraries. This tool bridges the gap instantly.
Paste your YAML into the input area and click Convert. The parser handles scalars, lists, nested mappings, and multi-line strings. The JSON output uses standard formatting with two-space indentation by default.
Use this when you have a config file you want to feed into a JSON-based tool, validate the structure of a YAML document, or quickly inspect what a YAML file actually contains.
Worked example
Convert a Docker Compose file snippet to JSON
- Copy the relevant section of your docker-compose.yml.
- Paste it into the YAML input area.
- Click Convert.
- Review the JSON output to confirm the structure matches your expectations.
A JSON object representing the same structure, with service names as keys and their configurations as nested objects.
Common mistakes to avoid
- Using tabs for indentation in YAML — YAML requires spaces; tabs cause a parse error.
- Pasting only a partial YAML snippet that starts mid-level without proper indentation context.
- Expecting YAML-specific types like timestamps to be converted to a JSON date type — they become strings.
Key terms
- YAML
- A human-readable data serialization format that uses indentation to represent nesting, commonly used for configuration files.
- YAML anchor
- A reuse mechanism in YAML (&name / *name) that lets a block be defined once and referenced elsewhere.
- Scalar
- A single plain value in YAML — a string, number, boolean, or null.
Frequently asked questions
- Is it safe?
- Yes — js-yaml's safe load is used and runs locally.