How many people shop online worldwide?

How to get close to this number

Take a share of internet users. This site's companion question puts internet users at around 5.5 billion, and roughly half of them have bought something online. Half of five and a half billion gives the answer, and chaining from a broader population through a participation rate is the standard method.

The national variation in the explanation is the part that matters: e-commerce is over forty-five percent of retail in one country and around twelve percent in another. Global averages for internet behaviour conceal differences of a factor of four between comparable economies, driven by logistics, payment systems and retail density rather than by internet access.

Retail density is the underrated factor. In countries where shops are walkable and close, online shopping competes against convenience it cannot beat; where retail is far away or sparse, it wins easily. The e-commerce share of a country tells you as much about its urban form as about its internet.