Los Angeles is about 20 times bigger than Pasadena.

Pasadena is approximately 59 sq km, while Los Angeles (including the city proper only) is approximately 1,215 sq km, making Los Angeles 1,943% larger than Pasadena.
Tip: This to-scale comparison of Pasadena vs. Los Angeles uses the Mercator projection, which distorts the size of regions near the poles.
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