Warsaw is about 4.7 times bigger than Bronx.

Bronx is approximately 109 sq km, while Warsaw is approximately 517 sq km, making Warsaw 373% larger than Bronx.
Tip: This to-scale comparison of Bronx vs. Warsaw 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.