They have a ninja population of about 20,000 because the alliance was about 80,000 and konoha having the biggest population probably contributed to the numbers the most while leaving behind enough ninja to protect the village and this who are to young. they probably have a civilian population twice this size. So the whole population is probably about 60,000 . Still probably not as big as Newyork
Yeah, my brother and I would always laugh when they showed just how big the Leaf was, yet characters kept calling it a "village."That's a lot bigger than any village. Anyway, I say about the size of a small modern city.