London is about 10 times smaller than Beijing.

Beijing is approximately 16,411 sq km, while London (including the 32 boroughs of greater London) is approximately 1,572 sq km, making London 9.58% the size of Beijing.
Tip: This to-scale comparison of Beijing vs. London uses the Mercator projection, which distorts the size of regions near the poles.
Our free app, MapSize by MyLifeElsewhere — compare any two places, to scale on your mobile device.