YAML Document — Human-friendly data serialization language using indentation.
Quick facts
What is .yaml
A .yaml file is a YAML Document — Human-friendly data serialization language using indentation.
In the mime-db registry it maps to text/yaml, and it is marked as compressible. When serving .yaml over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to text/yaml and is used by MiniYAML, OASv2-yaml among others — and is delivered over HTTP via the Content-Type header.
How to open .yaml files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: text/yaml
Common software that reads/writes .yaml:
Relation chain
Related extensions
Related MIME types
Related programming languages
Common uses
How to edit .yaml files
How to create .yaml files
Example
name: John age: 30 active: true
Frequently asked questions
Common options include VS Code, Python, kubectl. You can also open many of these files with built-in viewers or a browser.
Create a new file in any text editor or the app that owns the format and save it with the .yaml extension.
text/yaml is the media type identifier used for .yaml files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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