Mexico City is about 3.3 times bigger than Wellington.

Wellington (map shows its 57 named neighbourhoods; the area covers the whole city) is approximately 444 sq km, while Mexico City is approximately 1,485 sq km, making Mexico City 234% larger than Wellington.
Tip: This to-scale comparison of Wellington vs. Mexico City 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.