Index CFDs are sized in points, not pips: your position value per point times the stop in points is the money at risk. Futures contracts have fixed point values set by the exchange; CFD point values are set by your broker and vary.
About this calculator. The result is an educational estimate. Contract sizes, pip values, spreads, commissions and overnight financing differ by broker and by instrument, and fills can differ from the prices you model. Check your own account's specification before trading.