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YAML ↔ JSON Converter

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

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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

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.

What is YAML to JSON Converter?

YAML to JSON Converter parses structured configuration data and serializes it into the other format while preserving values and data types where both standards allow. It is useful for developers moving between readable configuration files, API payloads, and deployment manifests.

How to use YAML to JSON Converter

1.Paste YAML or JSON into the source editor and confirm or auto-detect the direction.
2.Choose the desired JSON indentation or YAML output options.
3.Convert the document and address any parser error at the reported location.
4.Review types, multiline strings, aliases, and null values before copying or downloading the output.

Key features

✓Automatic detection distinguishes JSON objects and arrays from typical YAML input.
✓Symfony YAML parsing handles standard mappings, sequences, scalars, anchors, and aliases.
✓JSON output supports configurable indentation and a deep but bounded nesting limit.
✓Unsafe object deserialization remains disabled during YAML parsing.
✓Swap controls make round-trip inspection convenient without re-pasting data.

Common use cases

Convert a Docker Compose fragment into JSON for an API.
Inspect a YAML CI configuration as a normalized object tree.
Prepare JSON application settings for a YAML-based deployment system.
Find an indentation or scalar-type problem in a configuration review.

Frequently asked questions

Are YAML comments preserved when converting to JSON?

No. JSON has no equivalent comment structure, so comments are lost when the parsed data is serialized.

Why did a quoted YAML value change after conversion?

The converter preserves the parsed type rather than the original typography. YAML implicit typing can turn some unquoted values into numbers, booleans, or null.

Does the converter support YAML anchors and aliases?

Standard anchors and aliases can be resolved by the parser, but the resulting JSON contains expanded data because JSON has no alias feature.

Is it safe to convert untrusted YAML?

Object deserialization is disabled, but untrusted or extremely large documents should still be handled cautiously and within the input limit.

Can JSON be converted back to identical YAML text?

The same data can be represented, but comments, quoting style, anchors, key styling, and exact whitespace cannot be reconstructed.

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