This century has witnessed the improvement of multi- collector- inductively coupled plasma mass spectrometry (MC- ICP- MS) and thermal ionization mass spectrometry (TIMS), which led to the breakthrough in analytical methods for many non- traditional stable isotopes (eg, Li, B, Mg, Ca, Mo, Cd, Fe and Zn). Accuracy of isotope measurement is dependent on proper correction methods for instrumental mass fractionation. The double- spike technique has been proposed as one of the most suitable correction methods for the precise and accurate measurement. However, complex mathematical calculations impede the application of this technique. This study designed a Microsoft Excel VBA based data reduction platform named “DS_CAL” for processing of double- spike technique data. The platform can conduct batch data input, element addition and parameter modification, and batch calculation for data obtained with the double- spike technique. The platform also provides two calculation models for stable and radiogenic isotopes. In addition, the calculation parameters (including the double spike composition) of DS_CAL can be flexibly modified. This study also shows an example of Mo isotope for the application of DS_CAL. This technique can be applied to all isotope systems that are suitable for double- spike technique which will promote its extensive application to isotopic analysis.