Below is a list of some of the best free APIs for generating charts.
1) Google Chart |
2) Flot |
The focus is on simple usage (all settings are optional), attractive looks and interactive features like zooming.Although Flot is easy to use, it is also advanced enough to be suitable for Web 2.0 data mining/business intelligence purposes which is its original application. |
3) Open Flash Chart |
Open Flash Chart is a Flash charting component. It is fairly easy to setup and has classes written in PHP, Perl, Python, Java, Ruby on Rails, and .Net to connect to the Chart. You can create some really nice looking Bar Charts, Pie Charts, Area Charts and etc… |
4) AmCharts |
5) PlotKit |
PlotKit is fully documented and there is a quick tutorial to get you started. PlotKit is a complete rewrite of CanvasGraph. It is better structured and supported. |
6) Flotr |
7) PHP/SWF |
You can use PHP scripts to generate or gather the data from databases, then pass it to this tool to generate Flash (swf) charts and graphs. Any other scripting language (ASP, CFML, Perl, etc.) can be used with XML/SWF Charts (the XML version of the same tool.)PHP/SWF Charts makes the best of both the PHP and SWF worlds. PHP scripts provide integration, and Flash provides the best graphic quality. |
8) Visifire |
9) FusionCharts |
10) JFreeChart |
developers to display professional quality charts in their applications.It has a flexible design that is easy to extend, and targets both server-side and client-side applications. It also supports many output types, including Swing components, image files (including PNG and JPEG), and vector graphics file formats (including PDF, EPS and SVG) |