Ukraine is about 773 times bigger than New York City.

New York City (including all five boroughs: Manhattan, Brooklyn, Queens, The Bronx, and Staten Island) is approximately 781 sq km, while Ukraine is approximately 603,550 sq km, making Ukraine 77,179% larger than New York City.
Tip: This to-scale comparison of New York City vs. Ukraine uses the Mercator projection, which distorts the size of regions near the poles.