Few different examples and built in shapes provided: line, circle and square. You can do your own animated SVG progressbar also by using ProgressBar.Path() to draw your own progressbar path.
Only 13KB JS file size to get started. Its really a nice SVG based progressbar script, 100% free and open source, hope it can give you some help in your projects.
Progressbar.js is released under MIT license.
Source: Read more about Progressbar.js