GoJS - GoJS is a JavaScript library for building interactive diagrams on HTML web pages. Build apps with flowcharts, org charts, BPMN, UML, modeling, and other visual graph types.
Pixi.js - Fast lightweight 2D library that works across all devices
mxGraph - mxGraph is a fully client side JavaScript diagramming library - jgraph/mxgraph
Snap.svg - Snap.svg is a javascript SVG library for the modern web.
JointJS - Create interactive diagrams in JavaScript easily.
Raphael - Raphael.js is an Object Oriented drawing library. It is good at making in-depth diagrams with complex interactions.