Washington is about 2.8 times smaller than Wellington.

Wellington (map shows its 57 named neighbourhoods; the area covers the whole city) is approximately 444 sq km, while Washington is approximately 158 sq km, making Washington 35.66% the size of Wellington.
Tip: This to-scale comparison of Wellington vs. Washington 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.