Which YAML library does this converter use?

This tool does not load external npm packages like js-yaml. It uses a custom built-in JavaScript recursive line parser and serializer implemented directly in the application source code.

Which YAML features are not supported by this engine?

Unsupported YAML features include YAML anchors (&anchor), aliases (*alias), custom type tags (!custom), multi-document streams separated by triple dashes, and binary byte buffers.

Are my configuration files or tokens sent to remote servers?

No. All conversion logic runs locally in browser JavaScript memory. No configuration values, secrets, or file contents are transmitted over network connections.

How does the converter handle multiline strings?

Multiline strings in JSON are serialized into YAML using literal block scalar syntax indicated by a pipe character, preserving newlines within the indented block.

Free & Private Online Browser Utility

JSON to YAML & YAML to JSON Converter Free

Convert data bidirectionally between JSON and YAML syntax directly inside your browser. This tool uses a custom JavaScript recursive serialization and line parsing engine without external npm YAML libraries. The jsonToYaml serializer formats nested dictionaries, lists, and primitives into clean YAML structures with configurable two-space or four-space indentation and quoted string safety checks. The parseYamlLines and parseYamlScalar engine traverses YAML indentation blocks, parsing scalars, key-value mappings, and hyphenated sequences back into valid JSON objects. Unsupported YAML features include YAML anchors and aliases using ampersand and asterisk syntax, custom schema tags, and binary types, which this custom parser deliberately omits. Processing occurs in browser memory without sending data to external networks.

How to use

Step 1: Paste JSON or YAML Data

Input raw JSON or YAML into the left editor pane, or use the file upload button to load a configuration file from your device.
Step 2: Select Direction and Indentation

Choose JSON to YAML or YAML to JSON conversion mode and set your preferred indentation spacing to two or four spaces.
Step 3: Copy or Download Converted Output

Inspect the transformed syntax in real time, copy the output to your clipboard, or download it as a .yaml or .json file.

Options explained

Indentation Spacing (2 Spaces vs 4 Spaces)

Sets the column offset applied to nested mapping keys and array sequences during JSON to YAML conversion.

When to use: Use two spaces for standard Kubernetes manifests and GitHub Actions workflows, or four spaces for Python-aligned configurations.

Direction Toggle

Switches the parser mode between JSON-to-YAML serialization and YAML-to-JSON parsing.

When to use: Use when converting application config files between REST API JSON payloads and cloud infrastructure YAML documents.

File Upload & Download

Reads local files via FileReader and saves converted text as downloadable file blobs.

When to use: Helpful when converting existing configuration files directly without manual copy-paste operations.

Worked example

Input: {"service": "api-gateway", "protocol": "https", "active": true}

Output: service: api-gateway protocol: https active: true

Example conversion; output format depends on your input structure.

Tips & limits

YAML relies strictly on indentation spaces; tabs are not permitted in standard YAML structures.
Unsupported YAML specifications such as anchors and aliases are not resolved by this custom client parser.
Because conversion runs client-side in browser RAM, server configurations and credentials are not transmitted externally.

Common problems

YAML parsing fails with indentation errors: Ensure indentation levels are consistent using spaces rather than tab characters throughout nested blocks.
Complex YAML anchors or custom tags do not parse: This lightweight engine supports standard primitives, lists, and key-value mappings; expand aliases before conversion.

Frequently Asked Questions (FAQ)

Which YAML library does this converter use?: This tool does not load external npm packages like js-yaml. It uses a custom built-in JavaScript recursive line parser and serializer implemented directly in the application source code.
Which YAML features are not supported by this engine?: Unsupported YAML features include YAML anchors (&anchor), aliases (*alias), custom type tags (!custom), multi-document streams separated by triple dashes, and binary byte buffers.
Are my configuration files or tokens sent to remote servers?: No. All conversion logic runs locally in browser JavaScript memory. No configuration values, secrets, or file contents are transmitted over network connections.
How does the converter handle multiline strings?: Multiline strings in JSON are serialized into YAML using literal block scalar syntax indicated by a pipe character, preserving newlines within the indented block.