Copenhagen is around the same size as The Hague (Den Haag).

The Hague (Den Haag) (excluding the city's 15.68 sq km of water area) is approximately 82 sq km, while Copenhagen is approximately 90 sq km, making Copenhagen 9% larger than The Hague (Den Haag).
Tip: This to-scale comparison of The Hague (Den Haag) vs. Copenhagen uses the Mercator projection, which distorts the size of regions near the poles.