Gibberish : Gibberish is designed to be a fast audio API for the browser. It takes the low-level building blocks provided by genish.js and uses them to create hig...
npoint.io : JSON storage bins with schema validation
Mockoon : Mockoon is the easiest and quickest way to design and run mock APIs. No remote deployment, no account required, free and open-source.
Public APIs : A collective list of free APIs for use in web development.
Bluepine is a DSL for defining API Schema/Endpoint with the capabilities to generate Open API (v3) spec, validate API request and serialize object for API response based on single schema definition.