FabricJS
Fabric.js is a powerful and simple Javascript HTML5 canvas library,
20 Alternatives To FabricJS
Draw2D
Create Visio like drawings, diagrams or an workflow editor with the Draw2D Javascript library.
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.
GraphicsJS
Free open-source JavaScript library for easily drawing HTML5 graphics and animation.
JavaScript InfoVis Toolkit
Interactive Data Visualization Library for the Web
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JointJS
Create interactive diagrams in JavaScript easily.
JsDiagram
Create interactive diagrams for JavaScript and HTML using MindFusion browser based visualization library.
PERGOLA
Pergola is a JavaScript SVG framework. It helps you create works ranging from the simplest presentations and User Interfaces to a complete Web Operating System (lazy loading on use of systemic components).
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PixiJS
Fast and flexible WebGL-based HTML5 game and app development library.
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Processing
C++ and Java programming at the speed of thought.
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Raphael
Raphael.js is an Object Oriented drawing library. It is good at making in-depth diagrams with complex interactions.
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StageXL
Create 2D games and apps with the Flash-like API for the Dart programming language.
Zdog
3D javascript engine for canvas and SVG
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mxGraph
mxGraph is a fully client side JavaScript diagramming library - jgraph/mxgraph
We created mxGraph in 2005 as a commercial project and it ran through to 2016 that way. Our USP was the support for non-SVG browsers, when that advantage expired we moved onto commercial activity around draw.
oCanvas
oCanvas is a JavaScript library intended to make development with HTML5 Canvas easier.