Prague is about 4.9 times bigger than Barcelona.

Barcelona is approximately 101 sq km, while Prague is approximately 496 sq km, making Prague 390% larger than Barcelona.
Tip: This to-scale comparison of Barcelona vs. Prague 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.