Today’s modern golf driver length with graphite shafts is about 45 to 45.5 inches for men, and 44 to 44.5 inches for ladies.
When you go about choosing a length that is right for you, it will be best to make the choice based on what is comfortable. You need a length that you can handle where you can hit the center of the face, so if 46 inches produce hit’s all over the face, then drop down to 45.5 inches. Sometimes a small change can make a big difference.
Hitting the center of the face in balance is much more important than going for a few extra yards with a driver length that's too long for you to handle with consistency. Some test suggested that a 2-inch length increase will only yield about 1 extra yard, so choose a driver length that you feel comfortable swinging while staying in balance.
You should also know that steel shafted drivers are an option and come in standard length that is about 2 inches shorter for the same swing weight as graphite. The main reason to consider a steel shafted golf driver is the extra static weight will help some golfers to control their tempo and not get too quick causing the wrong sequencing in their golf swing.