Does it support YAML anchors and aliases?

Yes, our converter handles YAML anchors (&) and aliases (*) by expanding them into full JSON structures.

What happens to YAML comments?

Since JSON does not support comments, all YAML comments are removed during conversion. The data structure is fully preserved.

Can I convert multi-document YAML?

Yes, YAML files with multiple documents (separated by ---) are converted to a JSON array containing each document.

Is the conversion order preserved?

Yes, the order of keys and items is preserved during conversion. YAML sequences become JSON arrays, and mappings become JSON objects.

YAML to JSON Converter – Convert YAML Online (Free Tool)

Convert YAML to JSON format instantly with this free online converter. Transform your YAML configuration files and data into valid JSON syntax with proper formatting. Ideal for developers working with configuration files, Kubernetes configs, and CI/CD pipelines. All processing happens locally in your browser.

What is YAML to JSON Converter?

YAML to JSON converts a YAML 1.2 document into compact JSON. Most runtimes, browser APIs, and HTTP clients consume JSON natively, so converting a human-authored YAML file into JSON is the last step before shipping config into an app. The parser handles flow style, block style, anchors, and references — the conversion runs entirely in the browser, so secrets in your YAML never leave the page.

Why use this tool?

100% free with no hidden costs or daily limits
Works offline after the first page load
Lightweight page weight that loads quickly even on slow connections
Built for developer workflows: copy-friendly output, syntax-aware highlighting where useful
Works with very large inputs (multi-megabyte JSON, long regex patterns, big tables)

How to use

Paste your input into the yaml to json converter area
Configure the options if the defaults don't match your case
Click the action button and inspect the result
Copy the output to your clipboard or download as a file

Examples

Compile a GitHub Actions matrix

A YAML matrix becomes a JSON array of objects you can paste straight into a custom CI tool that accepts JSON config.

Convert a Helm values file

Output JSON values can be fed into systems that don't understand YAML, like a JSON-schema validator or a JS templating engine.

Inspect anchor expansion

YAML anchors and aliases are inlined in the JSON output, making it easy to see what the final merged document actually looks like.

Common use cases

Feeding YAML config into JavaScript code that expects JSON
Validating YAML against a JSON Schema
Diffing two YAML files by converting both to canonical JSON
Migrating from YAML to JSON for performance (no YAML parser at runtime)
Pre-processing CI config before sending to a webhook or API

Troubleshooting

Conversion fails with "mapping values not allowed here".: Most often indentation is mixed (tabs and spaces). YAML strictly forbids tabs for indentation — replace with consistent spaces.
Strings like "on" or "off" became true/false.: YAML 1.1 booleans include many synonyms. Quote string values that look like booleans: 'off' becomes the string "off" in JSON.
Dates came out as ISO strings instead of objects.: JSON has no native date type. The converter serialises dates to ISO 8601 strings — parse with new Date(...) on the consuming side.

Frequently Asked Questions

JSON is widely supported by APIs, databases, and programming languages. Converting YAML config files to JSON makes them easier to consume in applications that expect JSON.

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