Brain.js

Brain.js is a JavaScript library used for neural networking, which is released as free and open-source software under the MIT License. It can be used in both the browser and Node.js backends.

Brain.js is most commonly used as a simple introduction to neural networking, as it hides complex mathematics and has a familiar modern JavaScript syntax. It is maintained by members of the Brain.js organization and open-source contributors.

Examples
Creating a feedforward neural network with backpropagation:

Creating a recurrent neural network:

Train the neural network on RGB color contrast: