The CAS Registry Mumber 126314-61-2 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,2,6,3,1 and 4 respectively; the second part has 2 digits, 6 and 1 respectively. Calculate Digit Verification of CAS Registry Number 126314-61: (8*1)+(7*2)+(6*6)+(5*3)+(4*1)+(3*4)+(2*6)+(1*1)=102 102 % 10 = 2 So 126314-61-2 is a valid CAS Registry Number.