The CAS Registry Mumber 326793-12-8 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 3,2,6,7,9 and 3 respectively; the second part has 2 digits, 1 and 2 respectively. Calculate Digit Verification of CAS Registry Number 326793-12: (8*3)+(7*2)+(6*6)+(5*7)+(4*9)+(3*3)+(2*1)+(1*2)=158 158 % 10 = 8 So 326793-12-8 is a valid CAS Registry Number.