The CAS Registry Mumber 14403-26-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,4,4,0 and 3 respectively; the second part has 2 digits, 2 and 6 respectively. Calculate Digit Verification of CAS Registry Number 14403-26: (7*1)+(6*4)+(5*4)+(4*0)+(3*3)+(2*2)+(1*6)=70 70 % 10 = 0 So 14403-26-0 is a valid CAS Registry Number.