Shanghai is about 31 times bigger than Oakland.

Oakland (map shows its 131 named neighbourhoods; the area covers the whole city) is approximately 202 sq km, while Shanghai is approximately 6,341 sq km, making Shanghai 3,039% larger than Oakland.
Tip: This to-scale comparison of Oakland vs. Shanghai 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.