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YAML to JSON Converter

Convert YAML to formatted JSON instantly. Supports nested objects, arrays, and configurable indentation — all processed in your browser.

// EXAMPLES

// YAML INPUT

Nothing is sent to the server — all processing happens in your browser.

// JSON OUTPUT

Paste YAML in the input panel to get started

What is YAML?

YAML(YAML Ain't Markup Language) is a human-readable data serialisation format designed for configuration files and data sharing. Unlike JSON, YAML uses indentation to define structure and supports comments, making it popular for infrastructure-as-code tools like Kubernetes, Ansible, and Docker Compose.

This converter uses JavaScript's built-in processing to transform YAML input into formatted JSON output. It handles nested objects, arrays, booleans, numbers, and null values — all without sending your data to any server.

When to Use YAML vs JSON

Use YAML for configuration:Kubernetes manifests, Ansible playbooks, Docker Compose files, CI/CD pipelines, and application settings all favour YAML for its readability and comment support.
Use JSON for APIs:REST APIs, webhooks, and inter-service communication use JSON because every language has a fast, mature JSON parser and the strict syntax eliminates ambiguity.
Convert YAML to JSON for tooling:Many tools that consume JSON cannot parse YAML directly. Converting your YAML config to JSON lets you validate it with JSON Schema, feed it to APIs, or use it in environments where only JSON is supported.

Frequently Asked Questions

Is my data sent to a server?: No. All conversion happens entirely in your browser using JavaScript. Your YAML data never leaves your device. Nothing is transmitted over the network.
Why does my YAML with comments produce JSON without them?: JSON does not support comments. When YAML is parsed, comments are stripped during the parsing step — they are not part of the data structure. This is expected behaviour: comments are for humans reading the YAML source, not for machines processing the data.
What happens with multi-document YAML files?: YAML supports multiple documents separated by --- within a single file. This converter does not support multi-document YAML and will display an error if it detects a --- separator. Combine your documents into a single YAML document before converting.
Why does YAML true become JSON true?: YAML recognises several literal values as booleans (true, false, yes, no, on, off) and null values (null, ~). The YAML parser converts these to their JSON equivalents: true, false, and null. This is correct behaviour — the data types are preserved, just the syntax changes.

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What is YAML?

When to Use YAML vs JSON

Use YAML for configuration:Kubernetes manifests, Ansible playbooks, Docker Compose files, CI/CD pipelines, and application settings all favour YAML for its readability and comment support.
Use JSON for APIs:REST APIs, webhooks, and inter-service communication use JSON because every language has a fast, mature JSON parser and the strict syntax eliminates ambiguity.
Convert YAML to JSON for tooling:Many tools that consume JSON cannot parse YAML directly. Converting your YAML config to JSON lets you validate it with JSON Schema, feed it to APIs, or use it in environments where only JSON is supported.

Frequently Asked Questions

Is my data sent to a server?

No. All conversion happens entirely in your browser using JavaScript. Your YAML data never leaves your device. Nothing is transmitted over the network.

Why does my YAML with comments produce JSON without them?

JSON does not support comments. When YAML is parsed, comments are stripped during the parsing step — they are not part of the data structure. This is expected behaviour: comments are for humans reading the YAML source, not for machines processing the data.

What happens with multi-document YAML files?

YAML supports multiple documents separated by --- within a single file. This converter does not support multi-document YAML and will display an error if it detects a --- separator. Combine your documents into a single YAML document before converting.

Why does YAML true become JSON true?

YAML recognises several literal values as booleans (true, false, yes, no, on, off) and null values (null, ~). The YAML parser converts these to their JSON equivalents: true, false, and null. This is correct behaviour — the data types are preserved, just the syntax changes.