How much office space is there in Manhattan?

If we can make a guess at how many people work in Manhattan, we can do some kind of office space per person. Some percentage of 10 million New Yorkers work in Manhattan, plus people who commute from outside the city. If we say two million people work in Manhattan, and each takes up 12 × 12 feet (144 sq ft), we can multiply and get 288 million square feet. That doesn't account for lobbies and bathrooms and whatnot, so it's probably undercounted. I will round up to 300~ million.

People working in Manhattan

~2,000,000

Space each, 12 × 12 ft

144 sq ft

2M × 144

≈ 288,000,000 sq ft

Round up for lobbies

≈ 300,000,000 sq ft

If we can make a guess at how many people work in Manhattan, we can do some kind of office space per person. Some percentage of 10 million New Yorkers work in Manhattan, plus people who commute from outside the city. If we say two million people work in Manhattan, and each takes up 4 × 4 meters (16 sq m), we can multiply and get 32 million square meters. That doesn't account for lobbies and bathrooms and whatnot, so it's probably undercounted. I will round up to 35~ million.

People working in Manhattan

~2,000,000

Space each, 4 × 4 m

16 sq m

2M × 16

≈ 32,000,000 sq m

Round up for lobbies

≈ 35,000,000 sq m