Seoul is about 1.5 times smaller than Indianapolis.

Indianapolis is approximately 935 sq km, while Seoul is approximately 605 sq km, making Seoul 64.73% the size of Indianapolis.
Tip: This to-scale comparison of Indianapolis vs. Seoul 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.