Buenos Aires is around the same size as Stockholm.

Stockholm (map shows its 47 named neighbourhoods; the area covers the whole city) is approximately 207 sq km, while Buenos Aires is approximately 203 sq km, making Buenos Aires 98.0% the size of Stockholm.
Tip: This to-scale comparison of Stockholm vs. Buenos Aires 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.