How Much Did King Kong Weigh?

The Empire State Building always brings to mind that iconic image of King Kong atop the skyscraper, swatting away biplanes as he clutches Fay Wray in his massive hand. But how massive? How much would the 1933-version of the mighty Kong have weighed?

King Kong, the 1933 movie

IMDb provides some relevant information on scale. Apparently, the size of the enormous ape varies from location to location and scene to scene. The publicity described Kong as 50 foot tall, but the sets in the jungle of his home island were consistent with an 18ft beast. The models for close-up photography of his hand were built to a scale that would fit a 40 ft animal, and the New York scenes were consistent with a 24 foot scale. Since it was the image of Kong on the Empire State Building that sparked this thought, let’s go with that figure, and treat him as 7.32 m tall.

If we take a Western Gorilla as the model for Kong when calculating height/weight ratios, we can scale up the height and use the square-cube law to scale up the weight. A very large gorilla of this species would be around 1.8m high and would weigh about 230 kg. So Kong was just over 4 times as tall as a very large gorilla, and using the cube of that ratio to scale his weight, we need a factor of 67.25 to give us a final mass of just under 15,500 kilograms. Does this seem reasonable? Three times as big as an elephant? I guess it does.

It’s entirely feasible that Kong would be scornful of the aircraft, since the planes used in the scene were Curtiss O2C-2 'Helldivers', which have a gross mass of a little over 2000 kg, around one eighth of his weight. But those annoying planes, equipped as they are with machine guns, finally cause the mighty Kong to lose his grip and tumble the 381 metres (52 times his own height), to the street below. And compared to that iconic building, the giant ape comes in at less than 1 / 20,000 of the mass of the Empire State Building itself, which is estimated to weigh 331 million tons.