Microsoft Office Tutorials and References
In Depth Information
You can access the credit card number validation workbook at this topic's website. The
file is named credit card validation.xlsx.
In this worksheet, the credit card number is entered in cell F1, with no spaces or hyphens. The formula in cell
F2 follows. This formula appends leading zeros, if necessary, to make the card number exactly 16 digits long.
The other formulas use the string in cell F2.
Figure 21-6: The formulas in this worksheet determine the validity of a credit card number.