JavaScript Chart Library

Question

There is a growing number of Open Source and commercial solutions for pure JavaScript charting that do not require Flash. In this response I will only present Open Source options.

There are 2 main classes of JavaScript solutions for graphics that do not require Flash:

• Canvas-based, rendered in IE using ExplorerCanvas that in turns relies on VML
• SVG on standard-based browsers, rendered as VML in IE

There are pros and cons of both approaches but for a charting library I would recommend the later because it is well integrated with DOM, allowing to manipulate charts elements with the DOM, and most importantly setting DOM events. By contrast Canvas charting libraries must reinvent the DOM wheel to manage events. So unless you intend to build static graphs with no event handling, SVG/VML solutions should be better.

For SVG/VML solutions there are many options, including:

• Dojox Charting, good if you use the Dojo toolkit already
• Raphael-based solutions

Raphael is a very active, well maintained, and mature, open-source graphic library with very good cross-browser support including IE 6 to 8, Firefox, Opera, Safari, Chrome, and Konqueror. Raphael does not depend on any JavaScript framework and therefore can be used with Prototype, jQuery, Dojo, Mootools, etc...

There are a number of charting libraries based on Raphael, including (but not limited to):

• gRaphael, an extension of the Raphael graphic library
• Ico, with an intuitive API based on a single function call to create complex charts

Disclosure: I am the developer of one of the Ico forks on github.

If you're using jQuery I've found flot to be very good - try out the examples to see if they suit your needs, but I've found them to do most of what I need for my current project.

Additionally ExtJS 4.0 has introduced a great set of charts - very powerful, and is designed to work with live data.

Check out http://www.highcharts.com !

Highcharts is a charting library written in pure JavaScript, offering an easy way of adding interactive charts to your web site or web application. Highcharts currently supports line, spline, area, areaspline, column, bar, pie and scatter chart types.

It maybe not exactly what you are looking for, but
Google's Chart API is pretty cool and easy to use.