PurposeTo assess the level of agreement and interchangeability among Excel and CMRtools (2012) for calculation of T2* values in iron overload.Materials and Methods T2* images in 27 cases withβ-thalassemia major were imported into CMRtools (2012). The regions of interest (ROI) were drawn and interference signal removed to obtain T2* values. The T2* images were also measured using default MR software and manually entered into Excel to obtain T2* values after removal of the interference signal. The agreement between the two methods in calculating T2* values was compared.Results For 27 patients withβ-thalassemia major, 10 cases showed myocardial iron overload. 25 cases had liver iron overload. The T2* values from two methods were not statistically significant (t=-0.152 and-0.691,P>0.05) for the liver.Conclusion There is good agreement and interchangeability between Excel and CMRtools (2012) in calculating T2* values. Excel can be used clinically to evaluate iron overload.