There are several ways to count lines and the one you are using is called by some a "gross" line . . . a line that is printed on the page. If you charge this way, your count will change according to font, font size, and margn widths. I don't charge this way because of that.When people speak of a 65-character line, they are speaking of counting 65 characters and space combined and calling it a line. It is a fair way of charging the client because you are always using the same unit of measure (the character) and this is never changed by font, font size, or margins.
One of my clients wants his work done in 10 pt Times New Roman, another in 10.5 Ariel, the third and fourth clients in 12 pt Times New Roman. I would be cheating myself if I charged the same for a 10 pt font as for the 12 pt.
None of my clients ever asked me how I determine a line. Yours may not either, but if they do, be sure you aren't cheating yourself. If you feel you must go with the printed line count, make sure you have written down how much you must charge for each different font size or you won't make much money.
My software doesn't count spaces, so I have to add them to my characters (words + sentences + paragraphs because each of these have a space behind them).
Hope this helps.
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