The Latte Line is an informal boundary that divides London's inner boroughs into two distinct social worlds. It loosely follows a corridor running south-west to north-east — separating the wealthier, more highly educated areas to the west and north from the historically working-class, more ethnically diverse neighbourhoods to the east and south.

The name references the prevalence of independent coffee shops and café culture as a proxy for gentrification and affluence. On one side: artisan espresso bars, high house prices, degree-holders. On the other: chicken shops, social housing, routine occupations — though that picture has itself been changing as gentrification pushes east.

This tool draws the boundary using a machine-learned composite score derived from Census data (education, occupation class, ethnicity), restaurant density, house prices, and deprivation indices across every LSOA in Greater London. The line is not fixed — it is a statistical snapshot. But the divide it traces is real.