Duck Key, FL -- U.S. Census Designated Place in Florida Population (2000): 443 Housing Units (2000): 828 Land area (2000): 0.861545 sq. miles (2.231390 sq. km) Water area (2000): 0.045243 sq. miles (0.117180 sq. km) Total area (2000): 0.906788 sq. miles (2.348570 sq. km) FIPS code: 18425 Located within: Florida (FL), FIPS 12 Location: 24.775623 N, 80.910972 W ZIP Codes (1990): Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Duck Key, FL Duck Key