How many tons does the International Space Station weigh?

How to get close to this number

Count the launches. The station was assembled from modules delivered over more than a decade, and a heavy-lift launch of that era could carry somewhere around twenty tonnes to orbit. Roughly twenty such deliveries gives a total in the hundreds of tonnes.

The size comparison in the explanation is the one that conveys it: roughly the area of a football pitch, mostly solar arrays rather than habitable volume. The pressurised living space is a small fraction of the structure, which is why the station looks far bigger in photographs than it feels inside.

The cost figure is the superlative worth keeping: an estimated hundred and fifty billion dollars, making it the most expensive object ever built. Divided by the mass, that is several hundred thousand dollars per kilogram — a price that only makes sense because until recently every one of those kilograms had to be launched on an expendable rocket.