Los Angeles is about 3.2 times bigger than Birmingham.

Birmingham (map shows its 87 named neighbourhoods; the area covers the whole city) is approximately 381 sq km, while Los Angeles (including the city proper only) is approximately 1,215 sq km, making Los Angeles 219% larger than Birmingham.
Tip: This to-scale comparison of Birmingham vs. Los Angeles uses the Mercator projection, which distorts the size of regions near the poles.
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