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YAML ↔ JSON Converter

Convert configuration and API data between YAML and JSON with automatic format detection.

Auto detect Safe validation Copy + download

Indent Auto Convert

Input

YAML or JSON detected automatically

JSON Output

Validated and formatted result

{
    "app": {
        "name": "SmartToolsNest",
        "environment": "production"
    },
    "features": [
        "formatter",
        "validator"
    ],
    "active": true
}

YAML converted to JSON.

Conversion Ready

How to Use

Paste YAML or JSON, use auto detection or select a direction, choose indentation, then copy, swap, or download the result.

Technical Specs

Parser: Symfony YAML
Input Limit: 2 MB
JSON Depth: 512 levels
Safety: No object deserialization

Configuration formats without manual rewriting

YAML is concise for human-edited configuration, while JSON is widely used by APIs and tooling. Conversion preserves structured mappings, lists, booleans, numbers, nulls, and multiline text.

Frequently Asked Questions

How does auto detection work? +

Input beginning with { or [ is treated as JSON; other structured input is parsed as YAML.

Are YAML comments converted? +

No. JSON has no comment representation, so YAML comments cannot survive a structural conversion.

Are anchors and aliases supported? +

Standard YAML parsing handles aliases, while unsafe object deserialization remains disabled.

Why do quoted values sometimes change? +

The converter preserves data types rather than the original textual styling.

YAML vs JSON Choose a configuration format Coming soon

YAML Indentation Rules Avoid common parse errors Coming soon

Safe Configuration Parsing Prevent unsafe object loading Coming soon

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