Lower
Purpose 
Returns all letters in text as lowercase.
Format 
Lower(text)
Parameters 
text - any text expression or text field
Data type returned 
text
Originated in 
FileMaker Pro 6.0 or earlier
Note
To change how a field displays without modifying its contents, see Text formatting functions.
Examples 
Lower(“ABCD”) returns abcd.
Lower(Course) returns history, when the Course field contains History.
Lower(“YOUR BILL IS OVERDUE”) returns your bill is overdue.
Related topics 
Functions reference (category list)
Functions reference (alphabetical list)
About formulas
About functions
Defining calculation fields
Using operators in formulas