Convert YAML to JSON Online Free

Convert YAML configuration files to JSON format instantly. Perfect for feeding config data into APIs, web apps, or any system that expects JSON input.

Quick Answer

To convert YAML to JSON, drop your .yaml or .yml file onto the converter. The conversion runs in your browser using js-yaml, producing valid, pretty-printed JSON with 2-space indentation. Your data stays on your device.

Free, no signup Files stay on your device Under 1 minute
100% browser-based
No file size limits
Works offline
No data uploaded

Convert YAML to JSON

Drop your YAML file here to convert it instantly

Drag & drop your .yaml file here, or click to browse

Your file never leaves your browser

YAML vs JSON: Format Comparison

Key differences between the two formats

FeatureYAMLJSON
SyntaxIndentation-based, minimal punctuationBraces, brackets, and commas
CommentsSupported with #Not supported
Native browser parsingNo, requires a libraryYes, JSON.parse() built in
Data typesRich (dates, binary, anchors, aliases)Basic (string, number, boolean, null, array, object)
API compatibilityRarely used directlyUniversal standard for APIs
Multiple documentsSupported with --- separatorNot supported (one root only)
StrictnessFlexible, whitespace-sensitiveStrict syntax rules

When to Convert

Common scenarios where this conversion is useful

API request bodies

Most REST APIs expect JSON payloads. Convert your YAML configuration into JSON to use in API calls, Postman collections, or fetch requests.

JavaScript and web applications

Browsers natively parse JSON but not YAML. Convert YAML data files to JSON for direct use in web applications without additional dependencies.

Database seeding and imports

Many databases and ORMs expect JSON for data import. Convert YAML data files to JSON for MongoDB imports, Firestore seeding, or Prisma seed scripts.

Validating YAML syntax

Converting YAML to JSON is a quick way to validate your YAML syntax. If the conversion succeeds, your YAML is well-formed.

How to Convert YAML to JSON

  1. 1

    Upload your YAML file

    Drag and drop your .yaml or .yml file onto the converter, or click to select it from your device.

  2. 2

    Automatic conversion

    Your YAML is parsed and converted to well-formatted JSON with proper indentation. Comments are stripped since JSON does not support them.

  3. 3

    Download the JSON result

    Click Download to save your converted .json file. The output is pretty-printed with 2-space indentation for readability.

Frequently Asked Questions

YAML comments (lines starting with #) are removed during conversion because JSON does not support comments. The data itself is fully preserved.

Yes. YAML anchors (&) and aliases (*) are resolved during conversion, producing the expanded JSON output with duplicated data where aliases were used.

YAML date values (like 2026-02-19) are converted to ISO 8601 date strings in the JSON output. If you need them as plain strings, quote them in your YAML source.

The converter processes the first YAML document in a multi-document file (separated by ---). For multiple documents, split them into separate files first.

The output is pretty-printed with 2-space indentation for readability. You can minify it afterward using any JSON minifier if needed.

Yes. If your YAML has syntax errors (incorrect indentation, invalid characters), the converter will report the error with the line number where the issue was found.

No. The conversion is entirely client-side. Your YAML data is processed in your browser and never transmitted anywhere.

Custom YAML tags (like !!python/object) are not supported and will cause an error. Standard YAML 1.2 types are fully supported.

YAML specification requires spaces for indentation, not tabs. If your file uses tabs, the converter will report a syntax error. Replace tabs with spaces first.

Yes, completely free with unlimited conversions. No registration, no email, no limits.

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