The Isogenic Game Engine allows you to create games in both 2d and isometric and has built-in isometric depth-sorting, path-finding and even supports Box2d in isometric!
LimeJS is a HTML5 game framework for building fast, native-experience games for all modern touchscreens and desktop browsers.
Jaws is a 2D game lib powered by HTML5. It started out only doing canvas but is now also supporting ordinary DOM based sprites through the same API.
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.
Hydrax/PBE is a game engine. It helps you write robust, maintainable, flexible games both big and small, having solved many problems that you will encounter if you don’t use this or a similar library.
ChesterGL (Chester Game Library) is a WebGL/canvas 2d game library that focuses on ease of use and performance. It supports a simple scene graph and provides a minimal interface for you to create games, and extend the library if you need. Current features: time based actions, simple scene graph, Tiled (tmx) map support, different shaders (webgl only), batched sprites.
Traffic Cone is a 2d and 2.5d (isometric) tile based game engine written for HTML5. It makes complex animations of sprites and tiles based worlds fairly simple.
UtimateJS is comprehensive HTML5 powered technology designed specifically to satisfy your cross-platform and cross-device game development needs.
UltimateJS is aiming to be the best HTML5 game engine as well for beginner as for professional programmers.
Collie can stably process multiple objects using rendering pipelines and supports useful features including sprite animation and user events. Stably supports iOS and Android, and renders with an optimized method for each platform. Also easily responds to retina display.
Irenic is an HTML5 game engine that can also aid server-side development, either for simulations or for game servers.
Squarepig is intended to be simple; as comfortable for novice developers making their first Web games as for experienced coders building demos and prototypes.
Construct 2 is a ground breaking HTML5 game engine. It lets anyone make games – without any programming experience.
The Playcraft Engine equips you with a complete HTML5 game engine toolset that gives you everything you need to build your game and take it directly to market. The Playcraft Engine is unique – once you write your game you can easily convert it to many different platforms, including Facebook, plain old websites, and as a native Android or iOS application.
GMP is great for making sprite-based, 2-D games, and it can easily power most retro-style arcade game designs. It is also well suited to making puzzles such as sudoku or gogopop. Check out the games on this site to see what it can do.
Professional game developers will find GMP useful for making rapid prototypes during their game development cycle. Set up is quick, and changes can be viewed by anyone with a browser.
Game hobbyists will find GMP easy to learn and hack. It’s simple enough to use as a learning tool, and powerful enough to run the back-end of production-quality games.