When highlighting a word in vim (Visual Mode), type:
In the command section of vim you'll see something like this:
Selected 1 of 90 Lines; 2 of 715 Words; 15 of 4171 Chars; 15 of 4173 Bytes
In this case,
15 of 4171 Chars is the number of total characters and the number of characters selected.
Its not as straight forward or as easy to parse as you might expect, but when you know what to look for it becomes easy to read.