Milwaukee is about 1.2 times bigger than Buenos Aires.

Buenos Aires is approximately 203 sq km, while Milwaukee is approximately 249 sq km, making Milwaukee 23% larger than Buenos Aires.
Tip: This to-scale comparison of Buenos Aires vs. Milwaukee 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.