Latex code and other tools for making neural networks diagrams

 PlotNeuralNet generates tikz code (for Latex) for illustrating a network architectures

NN-SVG is an online tool for illustrating simple architectures and that generates SVG code

Tensorspace.js is a web-based tool that takes keras network definitions and produces beautiful 3D representations on the browser that are also functional!

Netscope is a web-based tool for visualizing neural network architectures for the moment only supports Caffe's prototxt format

Have a look at the stackexchange thread about this topic: https://datascience.stackexchange.com/questions/12851/how-do-you-visualize-neural-network-architectures

Sources:

https://github.com/HarisIqbal88/PlotNeuralNet
http://alexlenail.me/NN-SVG/LeNet.html
https://tensorspace.org/html/docs/startHello.html
http://ethereon.github.io/netscope/quickstart.html
https://www.draw.io/ (for manual drawing from elementary shapes)