How many people live in the New York metropolitan area?

How to get close to this number

Take the city figure and apply a metro multiplier. The city proper is around eight and a half million, and large American metropolitan areas typically run two to three times their central city. That multiplier gives a figure approaching twenty million, which is right.

The comparison in the explanation is the useful one: more people than the entire Netherlands. Metropolitan areas of this size are effectively countries in population terms, and comparing them to nations is the fastest way to convey what the number means — a habit worth adopting for any figure above ten million.

The three-state spread is what makes the definition contentious. A metropolitan area is defined by commuting patterns rather than by borders, so the boundary is drawn by a statistical agency according to a methodology that occasionally changes. Metro populations can move by a million between definitions without a single person relocating.