331,000 t730,000,000 lb
The Empire State Building weighs about 331,000 tonnes (roughly 730 million lb). That is the building’s official figure of 365,000 US tons, converted to metric. It is the weight of the whole building, not just its steel frame, which accounts for about 57,000 US tons (about 51,700 tonnes) of the total.
The building’s official fact sheet says it weighs 365,000 tons. Like most American figures, these are short tons of 2,000 lb (907 kg), so the building weighs about 730 million lb, or about 331,000 metric tonnes. Read as metric tonnes by mistake, the same number would overstate the weight by about 10%.
The other tonnages quoted for the building are short tons too: 57,000 tons of structural steel (about 51,700 t), 10,000 tons of plaster (about 9,070 t) and 730 tons of aluminium and stainless steel on the facade (about 660 t). Wikipedia puts the steel actually ordered at 57,480 short tons, then the largest single steel order ever placed.
Steel is only about a sixth of the total. The rest is mostly masonry and concrete: 10 million bricks, 200,000 cubic feet (about 5,700 m³) of Indiana limestone and granite, and 62,000 cubic yards (about 47,400 m³) of concrete, according to the official fact sheet and the Skyscraper Museum.
The bricks and stone have no official weight, so the figures here are ours. A common brick weighs about 2 kg, which makes 10 million of them about 20,000 tonnes. Limestone weighs about 2.3 tonnes per cubic metre, so the facade stone comes to roughly 13,000 tonnes. The concrete is probably the heaviest single material: depending on the mix, 47,400 m³ would weigh somewhere between about 80,000 and 110,000 tonnes.
The fact sheet gives the building’s volume as 37 million cubic feet, about 1.05 million m³. Divide the weight by that and its average density is about 0.32 tonnes per cubic metre, roughly a third of the density of water. The air inside it weighs about 1,260 tonnes.
All that weight rests on a lot of about 79,000 square feet (7,370 m²). Spread evenly, it would press on the ground like a layer of water about 45 m (150 ft) deep. In practice the load goes down through the steel columns, 210 of which pass through each typical floor, to concrete footings set on the Manhattan bedrock about 55 ft (17 m) down. Four of the biggest columns, in the middle of the site, were designed to carry 10 million lb (about 4,500 t) between them.
Work on the building began on 17 March 1930 and it opened on 1 May 1931, one year and 45 days later. The steel frame rose at about 4.5 storeys a week and topped out at 1,048 ft on 19 September 1930, 23 weeks after the start of construction. At peak, about 3,500 workers were on site.
Every day, trucks delivered 16,000 partition tiles, 5,000 bags of cement, 450 cubic yards of sand and 300 bags of lime. The steel, mostly from Pittsburgh, was ordered and cut to size in advance. It was designed for a new city building code, signed just before construction began, that let steel carry 18,000 psi instead of 16,000, so the frame needed less of it.
About 730 million lb. That is the official figure of 365,000 US tons, at 2,000 lb per ton.
About 57,000 US tons of structural steel, or about 51,700 tonnes. That is only about 16% of the building’s total weight.
Its 102nd floor is 1,250 ft (381 m) up. Including the antenna, the building is 1,454 ft (443 m) tall.
Much heavier. The whole Eiffel Tower weighs about 10,100 tonnes, so the Empire State Building weighs about as much as 33 of them.
About 10 million. At roughly 2 kg each, they weigh about 20,000 tonnes in total, by our estimate.
Last checked October 3, 2026.
