GTIN-14 Check Digit formula

[KLOR]

I'm trying to calculate the check digit for a 13 digit upc. I found this formula, but it only allows up to 12 digits. When I try to add 13 and 14 so the formula calculates those digits also, the formula returns as "INVALID". Please help!

Number: 1076419513111 (should calc check digit 2)

Formula: =MOD(-SUM(MID(B1,{1,3,5,7,9,11;2,4,6,8,10,12},1)*{3;1}),10)
(results w/ 5, which is correct for a 12 digit number, but I need 13)

 

[Craig_Moore]

Hi GS1 have this freely available on there web site

Check digit calculator - Services | GS1

GS1 Check Digit Calculator can calculate the last digit of a barcode number, making sure the barcode is correctly composed. Calculate a check digit.

www.gs1.org

the image below shows the calculations and shows what the check digit should be