For small manufacturers with dedicated IT stuff, it is often a pain to write a trivial program. Numbers such as UPC-A, EAN-13, SCC-14, SSCC-18 and Bill of Lading (BLN) all require a modulo 10 check digit at the end. Although the algorithm is simple, it is easy to make mistaken if done by human. Fortunately you can now calculate check digits online using this free web utility. All you need is an Internet connection.