Google Chart Tools - Google Chart Tools is a world’s most popular tool that allows users to display their data on their website via simple or attractive visualizations.
GnuPlot - Gnuplot is a portable command-line driven interactive data and function plotting utility.
Google Data Studio - Data Studio turns your data into informative reports and dashboards that are easy to read, easy to share, and fully custom. Sign up for free.
GeoGebra - GeoGebra is free and multi-platform dynamic mathematics software for learning and teaching.
Chartio - Chartio is a powerful business intelligence tool that anyone can use.
SciDaVis - SciDAVis is a free application for Scientific Data Analysis and Visualization.