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.