Observe
You want to read the instrument: the argument, the cities, the global picture. Most people start here.
What the Fab City Index is
Every city that joins Fab City makes one promise: by 2054, produce almost everything it consumes. The Index shows which ones are actually moving.
For years, the only way to score a city on that promise handed nearly every large city the same answer: about 37 out of 100. Paris measured it in 2018. Hamburg landed on the same number in 2024, with a completely different system. When two cities six years apart get the same score, the score is telling you about the ruler, not the city. The Fab City Index is what we built after we stopped trusting a single snapshot and started reading a city the way you read a living system: what flows in, what goes out, and how fast it learns.
Three ways in
The Index is one window into a bigger instrument.
Most people come for one of three reasons. Pick yours and go straight to the part built for it.
Maintain data
You run a partner lab or lead a city's data. You connect the sources that fill the Index.
Run a campaign
Your community needs to create data no platform holds: sensing, surveys, the things people actually care about. This is the Making Sense model.
What the Index measures
A metabolism, not a snapshot.
Every city takes things in and puts things out. The old economy runs one way: products in, trash out. You buy what you need from far away and throw it away nearby. We call that PITO.
A Fab City runs the other way: data in, data out. It senses what is happening on the ground, shares designs and know-how openly, and makes more of what it needs close to home. We call that DIDO. The Index measures both, then adds the part no one else scores: how fast a city turns what it learns into action. A reading nobody acts on changes nothing. We call that speed ρ.
FCIt = DIDOt · (1 − PITOt) · ρt
The first two versions of the Index measured one slice of this, and measured it well. This version reads the whole picture: twenty parts of city life, for four real cities. The full method, weights and open gaps included, is on the methodology page.
The four pilots
One tool, four regions, honest about what is real.
Barcelona is our first real attempt at live data: its economic complexity, its fab-lab reach, the Smart Citizen sensor network, the city's open data portal. Boston, Santiago and Bali run in the same tool here, but their numbers are placeholders for now, and clearly labelled as such. The structure is real. The data is still being filled in.