Phoenix is about 3.6 times smaller than Auckland.

Auckland is approximately 4,894 sq km, while Phoenix is approximately 1,342 sq km, making Phoenix 27.43% the size of Auckland.
Tip: This to-scale comparison of Auckland vs. Phoenix 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.