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YAML to JSON Converter

Convert YAML data to JSON online in your browser. Paste YAML or open a .yaml or .yml file, review the converted JSON, and copy or download the result. Supports common mappings, sequences, nested structures, and multiline strings.

Converted JSON will appear here...
All processing happens in your browser. No JSON is sent to our servers.

Key Features

Paste or Open YAML Files

Paste YAML directly into the editor or open a .yaml or .yml file from your device. The converter is suitable for common configuration files and structured YAML documents.

Readable JSON Output

Convert YAML mappings and sequences into JSON objects and arrays, with formatted output that is easier to inspect, copy, and use in development workflows.

Configurable Indentation

Choose 2 spaces, 4 spaces, or a minified single-line JSON output. Formatted output is easier to review, while minified output keeps the result compact.

Conversion Error Details

Invalid YAML is reported instead of producing incomplete JSON. When the parser provides a location, the message includes the line and column where parsing stopped.

Multi-Document YAML

YAML documents separated by `---` are converted into a JSON array with one entry per document. A single YAML document is converted to a JSON object or array.

Copy or Download JSON

Copy the converted JSON to your clipboard or download it as a .json file for use in scripts, APIs, configuration workflows, and other JSON-based tools.

Browser-Based Processing

The conversion is performed in your browser and does not require an account or a server upload. For security, avoid entering passwords, API keys, tokens, or other highly sensitive secrets into any web tool.

How to Use

1

Enter or open YAML

Paste a YAML document into the input editor or open a .yaml or .yml file from your device. You can start with the included example if you want to test the converter first.

2

Choose output formatting

Select 2 spaces, 4 spaces, or minified output. Formatted JSON is easier to review, while minified JSON keeps the result compact.

3

Convert the document

Click Convert to JSON to parse the YAML and generate a JSON representation. Multi-document input separated by `---` becomes a JSON array. If the YAML is invalid, review the reported error and correction before converting again.

4

Copy or download the result

Review the generated JSON, then copy it to the clipboard or download it as a .json file. Check type conversions and multiline values before using the result in production.

Input
database:
  host: localhost
  port: 5432
  name: myapp
Output
{
  "database": {
    "host": "localhost",
    "port": 5432,
    "name": "myapp"
  }
}

How to Convert YAML to JSON Online

What Does a YAML to JSON Converter Do?

A YAML to JSON converter parses a YAML document and creates an equivalent JSON representation where the source structure can be represented in JSON. YAML is often used for configuration and deployment files, while JSON is common in APIs, JavaScript applications, and data-exchange workflows.

The conversion is not necessarily a byte-for-byte transformation. YAML and JSON have different syntax and feature sets, so comments, anchors, aliases, tags, document markers, and formatting choices may not be preserved in the JSON result.

Common Use Cases

  • Configuration conversion: Convert a YAML configuration into JSON for a script, application, or tool that expects JSON input.
  • Development workflows: Inspect YAML data as JSON while debugging integrations, APIs, or frontend code.
  • Kubernetes and Docker files: Convert valid YAML manifests or Compose configuration into JSON for inspection or downstream processing. This does not replace schema validation for the target platform.
  • CI/CD configuration: Convert pipeline-related YAML into JSON for custom analysis, reporting, or internal tooling where appropriate.
  • Data exchange: Prepare structured YAML data for a system or API that accepts JSON.

How YAML Maps to JSON

  • Mappings: YAML key-value mappings become JSON objects.
  • Sequences: YAML lists become JSON arrays while preserving their order.
  • Scalar values: Strings, numbers, booleans, and null-like values are converted according to the parser's YAML rules and JSON's supported value types.
  • Nested structures: Nested mappings and sequences become nested JSON objects and arrays.
  • Multiline strings: YAML block strings are emitted as JSON strings with JSON-compatible escaping.
  • Comments: YAML comments are generally not represented in standard JSON output.

How to Convert YAML to JSON

  1. Enter YAML: Paste a YAML document or open a .yaml or .yml file.
  2. Choose formatting: Select 2 spaces, 4 spaces, or minified output.
  3. Run the conversion: Click Convert to JSON and wait for the parser to generate the output.
  4. Review errors: If conversion fails, inspect the parser message and the reported line and column, then correct indentation, quoting, mapping syntax, or other invalid YAML.
  5. Copy or download: Copy the JSON or save it as a .json file for the next step in your workflow.

YAML Anchors, Aliases, and Multiline Values

YAML supports features that do not have direct equivalents in standard JSON. Anchors and aliases can describe reusable YAML nodes, but JSON has no native anchor syntax. When supported by the parser, these references are resolved into regular JSON-compatible values. As a result, the output may contain repeated values rather than preserving the original YAML references.

Literal and folded block strings, commonly written with | and >, are converted into JSON strings. Line breaks, trailing spaces, and folding behavior can affect the resulting text, so review important multiline values after conversion.

YAML Features That May Need Extra Checking

  • Comments: Standard JSON output does not preserve YAML comments.
  • Custom tags: Application-specific tags may not have a direct JSON representation.
  • Non-standard types: Dates, timestamps, binary values, and other YAML-specific types may be interpreted differently by different parsers.
  • Multiple documents: Documents separated by --- are converted into a JSON array with one entry per document, so a multi-document file no longer has to be split by hand.
  • Platform schemas: A syntactically valid conversion does not confirm that a Kubernetes, Docker, GitHub Actions, or other configuration file is valid for its target platform.

Checking the Converted JSON

After conversion, inspect values that are sensitive to type changes, including version numbers, dates, booleans, null values, numeric-looking strings, and multiline text. If the JSON will be used by a specific application, validate it against that application's schema or documentation rather than relying only on successful parsing.

Browser-Based Privacy

This page is designed to process YAML in the browser rather than upload it to a remote conversion service. That can reduce the need to transmit configuration snippets over the network, but it is not a substitute for secure secret management. Do not paste passwords, API keys, access tokens, private certificates, or production credentials into a browser-based tool. For highly sensitive data, use a trusted local command-line or desktop workflow instead.

Other Ways to Convert YAML to JSON

Developers may also convert files locally with a programming language library or a command-line utility such as yq. Local tools are often preferable for repeatable builds, automation, CI pipelines, and sensitive configuration. An online browser-based converter is most useful for quick inspection, one-off transformations, and development troubleshooting.

JSON Editor → JSON to YAML Converter →

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Frequently Asked Questions

Is my YAML uploaded to a server?

This page performs the conversion in your browser and does not require a server upload. You should still avoid entering passwords, API keys, access tokens, or other secrets into any browser-based tool.

Can I convert JSON back to YAML?

This page is focused on YAML to JSON conversion. If the site provides a separate JSON to YAML tool, use that tool for the reverse conversion. YAML and JSON are not always interchangeable in every advanced feature or formatting detail.

Can I upload a .yaml or .yml file?

Yes. You can open a .yaml or .yml file from your device, or paste the YAML text directly into the input editor.

Does the converter support nested YAML?

Yes. Standard nested mappings and sequences are converted into nested JSON objects and arrays, provided that the source YAML is valid and supported by the parser.

Does it support YAML anchors and aliases?

The result depends on the YAML parser used by the page. When anchors and aliases are supported, aliases are resolved into ordinary JSON-compatible values. JSON does not preserve YAML anchor declarations, so the original YAML relationships may not remain visible in the output.

Does it support multi-line strings?

Common YAML literal and folded block strings can be converted into JSON strings. Their line breaks and spacing may be represented differently because JSON has its own string escaping rules.

Can I output minified JSON?

Yes. Choose the minified indentation option to produce compact JSON without indentation or line breaks between tokens. The parsed data is unchanged; only the formatting differs.

Does the error message show a line and column?

When the YAML parser reports a location, the error includes the line and column where parsing stopped. Browsers may describe some YAML problems with a generic parser message, so use the location as a starting point rather than an exact definition of the mistake.

Can I convert multi-document YAML?

Yes. Documents separated by `---` are converted into a JSON array, with one array entry per document. Comments, anchors, and aliases are resolved by the parser and are not preserved as separate JSON constructs.

Can I convert Kubernetes or Docker Compose YAML?

You can convert valid Kubernetes manifests, Docker Compose files, CI/CD definitions, and other YAML documents as long as they use YAML features supported by the parser. The converter changes the data format; it does not validate the resulting file against Kubernetes, Docker Compose, or another product's schema.

Can I convert a large YAML file?

The practical file size depends on your browser, device memory, parser behavior, and document complexity. Very large files may take longer to parse or may exceed the available browser memory.

Why does my YAML fail to convert?

Common causes include inconsistent indentation, tabs used for indentation, missing colons, incorrect quoting, invalid document separators, and unsupported YAML features. Check the reported parser error and test the smallest failing section first.

Is this YAML to JSON converter free?

Yes. The converter is free to use without an account. You can paste YAML or open a file, generate JSON, and copy or download the result.