2 Answers

   It is difficult to imagine the size of the blue whale, the largest animal inhabiting the earth. There are records of individuals over 100 feet (30.5 m) long, but 70-90 feet (23-27 m) is probably average. A good way to visualize their length is to remember that they are about as long as three school buses. An average weight for an adult is 200,000 to 300,000 pounds (100-150 tons). Its heart alone is as large as a small car. Blue whales are an overall blue-gray color, mottled with light gray. Cold water diatoms adhere to their skin and sometimes give their bellies a yellowish tinge, giving the blue whale its nickname of "sulfur bottom." Blue whales are long and streamlined. Their dorsal fins are extremely small, and their pectoral flippers are long and thin. Blue whales are rorqual whales, a family of baleen whales with pleated throat grooves that expand when the animal takes in water while feeding. In blue whales, 55-68 throat grooves extend from the throat to the navel. Blue whale baleen is black with over 800 plates.

http://www.marinemammalcenter.org/education/marine-mammal-information/cetaceans/blue-whale.html

Or, set him on your foot, and multiply the pain, and convert it to pounds of weight!