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Sensitivity related routines (experimental design, data and model resolution analysis, nonlinear least squares inversion) on the Magnetotelluric data require accuracy and cost-saving in time especially when huge data set and model parameters are involved. The common approach for the computation of the sensitivity matrix for inverting the 1D Magnetotelluric data is via a numerical approach because its formulation is simple to design and to implement. However, the differentiation of the recursive sequence of Magnetotelluric forward response (Cagniard apparent resistivity and phase) makes the speedy analytical computation of the sensitivity matrix handy at different frequencies. The MATLAB code for the computation is presented and it should be useful further research and production purpose.