What does the parser output?

A JSON tree equivalent to the YAML input. Use this to feed YAML into JSON-only tools (validators, queriers, transformers) or to inspect the resolved data structure.

Does it resolve anchors and references?

Yes by default — `*ref` aliases are replaced with the actual referenced value. Toggle off to preserve them (useful for round-tripping).

How are custom tags handled?

Unknown tags pass through as annotated values you can inspect. This is safer than throwing, which would stop parsing at the first custom tag.

What about multi-document YAML?

Each `---` separator creates a new document; the parser returns an array of documents. Single-document input returns a single value, not wrapped.

YAML Parser | DevTools Surf

DevTools Surf

Example: YAML Parser

A worked example, rendered from real sample data. Sign in to run the tool on your own input.

Input

server:
  host: localhost
  port: 8080
  ssl: true
database:
  url: postgres://localhost/mydb

Output

{
  "server": {
    "host": "localhost",
    "port": 8080,
    "ssl": true
  },
  "database": {
    "url": "postgres://localhost/mydb"
  }
}

About YAML Parser

Parse YAML and extract structured data. Part of the DevTools Surf developer suite. Browse more tools in the YAML collection.

Use Cases

Backend devs extracting values from complex YAML config files
DevOps engineers parsing Helm chart templates programmatically
Data engineers converting YAML data sources to internal structures
Automation engineers reading YAML-based test fixture definitions

Tips

Check that multi-document YAML files parse all documents correctly
Verify that anchors and aliases resolve to expected values
Review parsed output for unexpected type coercions like booleans

Fun Facts

YAML supports multiple documents in a single file, separated by '---', a feature heavily used in Kubernetes and Jekyll.
YAML parsers must handle 9 scalar styles: plain, single-quoted, double-quoted, literal block, folded block, and 4 flow variants.
The PyYAML library, one of the most popular YAML parsers, was first released in 2006 and has been downloaded over 1 billion times.

FAQ

What does the parser output?: A JSON tree equivalent to the YAML input. Use this to feed YAML into JSON-only tools (validators, queriers, transformers) or to inspect the resolved data structure.
Does it resolve anchors and references?: Yes by default — `*ref` aliases are replaced with the actual referenced value. Toggle off to preserve them (useful for round-tripping).
How are custom tags handled?: Unknown tags pass through as annotated values you can inspect. This is safer than throwing, which would stop parsing at the first custom tag.
What about multi-document YAML?: Each `---` separator creates a new document; the parser returns an array of documents. Single-document input returns a single value, not wrapped.

Related YAML Tools

YAML Validator YAML Viewer YAML Formatter YAML Multi-Doc Splitter YAML Anchor Expander XML Parser .env → YAML API Documentation from Code