Tesseract.js is a pure Javascript port of the popular Tesseract OCR engine.
LittleJS is a lightweight 2D JavaScript game engine with fast WebGL rendering. It was designed to be small, simple, and easy to use for various applications, from game jams to commercial releases.
Zdog is a 3D JavaScript engine for <canvas>
and SVG. You can design and render simple 3D models on the Web. Zdog is a pseudo-3D engine. Its geometries exist in 3D space, but are rendered as flat shapes.
PixiJS is the HTML5 creation engine that you can create beautiful digital content with the fastest, most flexible 2D WebGL renderer.
Proton is a lightweight and powerful javascript particle engine that can easily create countless cool effect.
Matter.js is a 2D rigid body physics engine for the web written in JavaScript.
Planck.js is a 2D JavaScript physics engine for cross-platform HTML5 game development.
Styletron is a universal CSS-in-JS engine built from the ground up for high-performance.
Anime is a flexible yet lightweight JavaScript animation library. It works with CSS, Individual Transforms, SVG, DOM attributes and JS Objects.