Lake Okeechobee - Surface area: 730 square miles.
The second largest lake entirely within the US is Lake Iliamna, Alaska, at 1000 sq miles. Lake Okeechobee in Florida is 700 sq miles
Surface area of Lake Michigan = 22400 sq miles.
Hemlock Lake covers 2.812 sq miles (7.284 km²).
Lake Michigan covers an area of 22,394 sq miles (58,000 km²).
Ontario is approxiamately 415,600 sq. miles.
The Top 10 Largest Lakes in North America, as stated by Nation Master are: 1. Lake Superior, Canada/United States - 82,410 km2 (31,820 sq miles) 2. Lake Huron, Canada/United States - 59,600 km2 (23,010 sq miles) 3. Lake Michigan, Canada/United States - 57,080 km2 (22,040 sq miles) 4. Great Bear Lake, Canada - 31,000 km2 (12,000 sq miles) 5. Great Slave Lake, Canada - 28,930 km2 (11,170 sq miles) 6. Lake Erie, Canada/United States - 25,700 km2 (9,930 sq miles) 7. Lake Winnipeg, Canada - 23,550 km2 (9,094 sq miles) 8. Lake Ontario, Canada/United States - 19,500 km2 (7,520 sq miles) 9. Athabaska Lake, Canada 7,920 km2 (3,058 sq miles) 10. Reindeer Lake, Canada 6,330 km2 (2,444 sq miles)
Lake Superior; and it is about 31,820 sq miles. (82,400 sq km)
Surface area of 9,940 sq mi (25,700 km2]
Lake Ontario is 7,340 sq miles in area.
Lake Chad
It covers 26600 sq miles.
Lake Baikal covers 12,248 sq miles, making it the world's 7th biggest lake (if you consider the Caspian Sea as a lake, which many people do )