To uppercase only the first letter in a cell in Excel, you can use the following formula:
=UPPER(LEFT(text_cell,1))&LOWER(RIGHT(text_cell,LEN(text_cell)-1))
For a sample string: “THIS is A SaMPLE StRIng.”
The result will be:
"This is a sample string."
A visual is below for your reference:
If you want to instead capitalize the first letter of each word in a cell, or uppercase/lowercase all characters in a cell, Excel already has some prebuilt formulas to do so.
For more questions about capitalization, use our free title capitalization tool.