The viewable rectangular screen size dimensions for an exactly 42″ diagonal television would be about 36.6″ wide and 20.6″ high. Actual 42″ TV screen dimensions may vary slightly by a fraction of an iNCH more or less, as TV screen size classes are rounded to the nearest whole iNCH. Also, the bezel adds a bit more width and height to the television’s overall dimensions, and two supporting legs/feet or a pedestal stand add some more height and depth if you don’t wall mount the TV.