Gauss coordinates are widely used in our army's battle command information system because of their intuitive and simple calculation. Manual inputs of invalid coordinates whose values exceed the boundary will often reduce the combat efficiency of the system, or lead to serious problems such as shooting parameters calculation errors in the system. The Gaussian projection formula shows that there is a strong correlation between the abscissa and ordinate components, the two coordinate components are constrained by each other and the mapping relationship is complex. Considering the existence of a large number of low-performance hardware environments such as handheld terminals in the system, it is necessary to study the accurate and fast solution algorithm of the Gaussian coordinate range in the CGCS2000. Through the analysis of Gaussian projection principle, when the Gaussian ordinate is known, the step-by-step approach iterative algorithm can be used to realize the accurate calculation of the value range of Gaussian abscissa, or the least square method can be used to realize the fast calculation; When the Gaussian abscissa is known, the half search algorithm can be used to accurately calculate the value range of Gaussian ordinate, or the combination of least square method and half search algorithm can be used to realize fast calculation. Through the data comparison and analysis of a large number of calculation results, the calculation accuracy and speed meet the requirements,and relevant tool software is developed,which is suitable for engineering implementation and application.