Waxing is a form of semi-permanent hair removal which removes the hair from the root. New hair will not grow back in the previously waxed area for two to eight weeks, although some people will start to see regrowth in only a week. Although the results are fairly similar, there's one key difference: how long they last. On average, waxing lasts around 3 or 4 weeks because the hair is removed at the root. Hair grows back much faster with shaving, though — within 3 days to a week. This is because shaving only removes the top layer of the hair.