Hii wonder is there a tools/lisp on AutoCAD that compute area between contours?i've try to create polygon using "BPOLY" command, but it can't create an inner area between them. since it "overlap" all the area inside first polygon.i also have looking for GIS solution (such as ArcGIS) but can't find the solution (I stuck on converting the unit that ArcGIS provided)any help will appreciate, thanks.    

Hello irpanch, you can find the area defined in the middle of the three contours by different means, for example :-1- Use the command REGION and SUBTRACT and you will have it, but it will maybe erase the external contour.-2- Use the command HATCH and it will fill the contour that you want without destroing the others, then you use LIST or the properties pallette ( CTRL + 1 ) to read the result.