Tom’s Tutorials For Excel: Forcing Entries in UPPER Case
Here’s how you can force users to enter all alpha (letter) characters in UPPER case, using Data Validation and no programming code.
To make this happen, press
Alt+D+L on your keyboard to show the Data Validation dialog box.
Next, follow the pictured sequence, and note the formula
=EXACT(A1,UPPER(A1)) being used, because A1 is the demonstration cell in this example.