Convert YAML to JSON online, free. YAML is an indentation-based superset of JSON favoured for human-edited config. JSON is the dominant data-interchange format for web APIs and config. YAML to JSON conversion parses your YAML against the YAML 1.2.2 grammar (https://yaml.org/spec/1.2.2/), builds an in-memory model of its keys, nested objects and arrays, then re-serializes it as valid JSON following the ECMA-404 / RFC 8259 conventions. Processing runs in your browser in JavaScript with no upload or server round-trip — no size limit beyond your device's memory, so multi-megabyte documents convert in milliseconds and sensitive payloads never leave your machine. Typical uses include REST/GraphQL API payloads, app & build configuration and logging and analytics events.
It maps the full structure of your YAML onto well-formed JSON, following the ECMA-404 / RFC 8259 conventions. 100% free, no registration, and complete privacy — everything runs locally in your browser, so your data never touches a server.
Paste YAML and convert JSON immediately. Conversion runs client-side, so there is no upload wait and large documents stay fast.
Nested YAML objects, tables and arrays are mapped faithfully onto JSON.
Your YAML never leaves your device — everything is processed locally in JavaScript, with nothing logged or stored.
Unlimited conversions with no account, no quotas, and no watermark. Works on desktop and mobile.
A YAML document and its JSON equivalent:
YAML input:
name: Alice
age: 30
email: [email protected]Output:
{
"name": "Alice",
"age": 30,
"email": "[email protected]"
}Paste your YAML into the editor and press "Convert to JSON". The tool parses it against the YAML 1.2.2 grammar, then re-serializes it as JSON following ECMA-404 / RFC 8259 conventions — instantly and entirely in your browser. You can validate or format the YAML first to be sure it is clean.
YAML anchors and aliases are expanded and comments are dropped before JSON is produced, and indentation defines the structure. Note that YAML 1.1 treats words like "yes" and "no" as booleans, so quote them if you want strings.
Numbers, booleans and null are preserved as native JSON types wherever JSON supports them, so standard documents convert losslessly and can be read back into the same structure.
YAML (YAML Ain't Markup Language) (YAML) — YAML is an indentation-based superset of JSON favoured for human-edited config. JSON (JavaScript Object Notation) (JSON) — JSON is the dominant data-interchange format for web APIs and config. This converter maps the structure of your YAML onto JSON so you can use it for REST/GraphQL API payloads.
Yes. Invalid YAML is flagged with a clear error before anything is converted. Common YAML problems to check are spaces (never tabs) for indentation, consistent indent levels, and no duplicate keys. Starting from clean input keeps the generated JSON accurate.
Yes. The entire YAML-to-JSON conversion runs locally in your browser in JavaScript — your YAML is never uploaded, logged or stored. That matters when the data is something like Kubernetes & Docker Compose manifests, which should not leave your machine.
The generated JSON is ready for REST/GraphQL API payloads, app & build configuration and logging and analytics events. Copy or download it and drop it straight into your tooling.
YAML to JSON conversion parses a YAML document and emits the equivalent JSON. YAML ("YAML Ain't Markup Language") is a human-friendly, indentation-based data format popular for configuration (Kubernetes, Docker Compose, CI pipelines), while JSON is the format APIs and JavaScript consume natively. The two share the same underlying data model — maps, sequences, and scalars — so conversion is lossless for standard documents. This tool parses YAML to the YAML 1.2 specification and produces clean, indented JSON entirely in your browser.
For standard documents, yes — YAML and JSON share the same data model, so maps, lists, and scalars convert one-to-one. YAML-specific extras like comments and anchors are resolved away in the JSON output.
YAML uses indentation and is optimized for human editing; JSON uses braces and brackets and is optimized for machine parsing. JSON is actually a subset of YAML 1.2.
No. Conversion runs entirely in your browser — your data never leaves your device.
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