YAML to JSON
Convert YAML to JSON format. Supports indentation levels, key-value pairs, lists, and nested structures — all in your browser, no upload, instant results.
About the YAML to JSON Converter
This YAML to JSON converter runs entirely in your browser. Paste YAML into the box above and click Convert. The result appears as formatted JSON. Nothing is uploaded to a server — the conversion happens instantly with JavaScript on your device.
About the YAML format
YAML (YAML Ain't Markup Language) is a human-friendly data serialization format. It uses indentation to express nesting, dashes for list items, and key: value pairs for mapping entries. It is widely used for configuration files.
Parsing rules
- Indentation — Spaces define nesting. Two spaces per level is conventional; tabs are not allowed in YAML indentation.
- Key-value pairs — Written as
key: value. The space after the colon is required. - Lists — Items start with
-at the same indentation level. - Nested structures — Mappings and sequences may be nested arbitrarily.
- Scalars — Strings, numbers, booleans, and null are auto-detected where unambiguous.
Common use cases
- Converting configuration files for use in JavaScript applications.
- Inspecting YAML data structures in JSON form.
- Migrating YAML-based settings to JSON APIs.
- Quick validation of YAML syntax.
Frequently asked questions
Does this tool upload my YAML? No. All conversion happens locally in your browser. Your data never leaves your device.
Are tabs allowed for indentation? No. The parser uses spaces, consistent with the YAML specification. Tabs in indentation will cause an error.
Are comments supported? Lines starting with # are treated as comments and ignored.
Is there a size limit? The only limit is your browser's available memory. Even large YAML files convert quickly.