Boston is about 1.8 times smaller than Dusseldorf.

Dusseldorf is approximately 217 sq km, while Boston is approximately 124 sq km, making Boston 57.04% the size of Dusseldorf.
Tip: This to-scale comparison of Dusseldorf vs. Boston 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.