Turbulenz Engine
Turbulenz is a modular 3D and 2D game framework for making HTML5 powered games for browsers and mobile devices.
PhysicsJS
A modular, extendable, and easy-to-use physics engine for javascript
Phaser
Phaser is a light-weight 2D game framework for making HTML5 games for desktop and mobile browsers
Canvas Engine
Framework for HTML5 Canvas oriented 2D video games
Babylon.js
Babylon.js: a complete JavaScript framework for building 3D games with HTML 5 and WebGL
Enchant.js
A simple JavaScript framework for creating games and apps
Gamejs
GameJs is a thin library on top of the HTML canvas element. In addition to the drawing functions it has a set of generally helpful modules for game development.
Coquette
A micro framework for JavaScript games
Chem
html5 game engine optimized for rapid development
Pixi.js
Super fast HTML 5 2D rendering engine that uses webGL with canvas fallback
Joy.js
A Joyful 2D HTML5 Game Engine.
Easystar.js
An asynchronous A* pathfinding API written in Javascript.
Keydrown
A JavaScript key state handler for web apps
Flash JS
JavaScript graphics and games engine with API familiar to Flash one. Just look to examples sources.
Verlet JS
A simple Verlet physics engine written in javascript
Melon JS
a fresh & lightweight javascript game engine
Limejs
HTML5 game framework for web and iOS