Portland is about 9 times smaller than Prague.

Prague is approximately 496 sq km, while Portland (map shows its 17 named neighbourhoods; the area covers the whole city) is approximately 56 sq km, making Portland 11.24% the size of Prague.
Tip: This to-scale comparison of Prague vs. Portland 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.