Sources suggest that the average house fly is 6 to 7 mm long and weighs around 12 mg. An average man is 177cm (1770 mm) tall and weighs 65-67kg (65,000,000 - 67,000,000 mg).
Therefore an average human is around 295 to 253 times taller and around 5,416,667 to 5,583,333 times heavier than a house fly.
The house fly, Musca domestica Linnaeus, is a well-known cosmopolitan pest of both farm and home. This species is always found in association with humans or the activities of humans. It is the most common species found on hog and poultry farms, horse stables and ranches.
It may be the most common insect people encounter. But how much do you really know about the house fly? Here are 10 fascinating facts about house flies you may not know shared by About.com.