A large quantity of published data is available only in the form of plots and it is often difficult to extract numerical data accurately out of these pictures. There are several softwares available to aid this process, but most are either paid or poorly written.
Cost / License
- Free
- Open Source (AGPL-3.0)
Platforms
- Online



WebPlotDigitizer is the most popular Web-based alternative to GraphClick.
WebPlotDigitizer is the most popular Open Source & free alternative to GraphClick.
- WebPlotDigitizer is Free and Open Source










































Graph click allows you to specify the axes coordinates one axis at a time. Engauge requires that you know both coordinates along each axis. This is not often possible. I have a graph where I don't know the x and y coordinates for the axes -- just one or the other. For certain types of graphs, Engauge is useless.