Why cost per kilogram is the number that matters
Dollars per kilogram to orbit is the single figure that decides what becomes possible in space — and it has fallen ~20× since the Shuttle. We explain the number and why headline prices need caveats.
Almost every ambition in space — bigger constellations, crewed missions, eventually heavy industry off Earth — is gated by one number: how many dollars it costs to put one kilogram into low Earth orbit. When that number falls, things that were uneconomic suddenly pencil out.
The drop has been dramatic. The Space Shuttle cost on the order of $54,500 per kilogram. A reused Falcon 9 is commonly cited around $2,600 per kilogram — roughly a twentyfold reduction — and Starship aims far lower still, with SpaceX targeting figures that, if achieved at high flight rates, would be another order of magnitude down.
Two caveats keep this honest. First, quoted prices are not costs: a customer's price reflects market position, not just what the launch costs the provider, so the same rocket can be described with very different numbers. Second, the lowest figures for Starship are targets, not invoices. The tracker shows the publicly cited price for the cheapest flying option and marks the goal separately, so the distance between today's number and the promise stays visible.