Converting A Cell Entry into a Set # of Characters

[carl]

Can I take the following values and convert them all to 3
character length ?

A
AB
ABC

A would become A__ (A,space,space)
AB would become AB_
ABC stays the same ABC

Thank you in Advance

 

[Frank Kabel]

Hi
in an adjacent column enter
=A1 & REPT(" ",MAX(3-LEN(A1),0))

 

[Peo Sjoblom]

Using a help column

=A1&REPT("_",3-LEN(A1))

copy down

then paste special as values over the old ones or in place

(note that I used the underscore as in your example and not a space,
just replace it)