Ducks and peafowl aren't precision machines. Individuals don't always produce the exact same size of egg each time. Egg size depends on a hen's age, health and breed. In general, though, peafowl eggs are larger than duck eggs.
The generally accepted standard for egg size comparisons is a large chicken egg -- the kind sold in the grocery store. Both peafowl and duck eggs are larger than chicken eggs. Duck eggs are only slightly larger than chicken eggs but can be distinguished by the waxy exterior coating and thick shell. Duck eggs have much larger yolks than chicken eggs. Peafowl eggs are larger than both chicken and duck eggs. They are about 50 percent larger than chicken eggs and are about the same size as turkey eggs but smaller than emu or ostrich eggs. In a side-by-side comparison, it's easy to observe the difference in size between chicken, duck and peafowl eggs.
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