Ask HN: Your favorite open-source JavaScript Library for charts?

I like http://c3js.org/ - it's built on top of D3.

The one I use is HighCharts [1]

Very clean and very good.

[1] - http://www.highcharts.com/

http://plot.ly does everything I've ever wanted and more with pretty good API. The fact that I can use the same API first for doing data exploration in python or R and then when publishing the results to the web is a nice added bonus.

Try the Github showcases that lists all the major ones https://github.com/showcases/data-visualization

NVD3's pie chart[1] is quite straightforward, some of the other charts in the library need work though.

[1] - http://nvd3.org/examples/pie.html

After using several different libraries over the past few years, I've started using D3.js on its own. While it's more work than dropping something ready-made into an app, it's more flexible.

If you have specific designs/requirements to work from, it may be easier to build the charts with D3 than trying to shoehorn a stock chart into matching the spec. Behaviors like linking chart interactions to independent components (or vice versa) become easier to implement as well.

If you care less about flexibility, Chartist is a solid contender: https://gionkunz.github.io/chartist-js/

Thanks for your recommendations.

I'm currently taking a look at all the libraries and will test the functionality over the next days. Some of them are realy overweighted - especially the D3-based libs seem to be slower than the others.

I'll keep you informed about my "test winner".