London is about 135 times smaller than Utah.

Utah is approximately 212,751 sq km, while London (including the 32 boroughs of greater London) is approximately 1,572 sq km, making London 0.74% the size of Utah.
Tip: This to-scale comparison of Utah 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.