The list is sorted alphabetically by state followed by alphabetically by county for each state. The answer also contains Washington D.C. (as District of Columbia) and Puerto Rico as obtained from census.gov at the bottom.
Note: You can use your browser's built-in search function to search this list. Use the shortcut CTRL+F and type in the name of the county in the search. It will take you to each instance of that county name as some counties do have the same name in different states.
Alabama: 4,627,851It depends on the population of the county
The smallest county by population in Wyoming is Niobrara County with 2,484 people (2010 US Census).
Dade County is a county located in Florida. It is the third largest county in Florida. According to the 2010 US Census, Dade County had a population of 2,496,435.
Los Angeles County which has a population of 9,818,605. The county itself is more populous than 42 states.
According to the 2000 US Census, the population of Ventura County, California was 753,197.
In area, Sweetwater County is the largest county in Wyoming with a total area of 10,491 square miles (27,172 km²), of which 10,425 square miles (27,001 km²) is land and 66 square miles (171 km²) (0.63%) is water. Sweetwater county is also the 8th largest county in the US. By population, the largest county in Wyoming is Laramie County with a population of 91,738 according to the 2010 US Census.
The most populated county in the US is Los Angeles County in California with a total population of 9,878,554.
That depends entirely on which Duval County you are requesting information about. There are two Duval Counties in various states across the US. According to census.gov, the 2007 estimated total population of each of these Du Counties and which state they are located in are listed alphabetically as follows:# Duval County, Florida: 849,159 # Duval County, Texas: 12,187
That depends entirely on which Clayton County you are requesting information about. There are two Clayton Counties in various states across the US. According to census.gov, the 2007 estimated total population of each of these Clayton Counties and which state they are located in are listed alphabetically as follows:# Clayton County, Georgia: 272,217 # Clayton County, Iowa: 17,685
That depends entirely on which Osage County you are requesting information about. There are three Osage Counties in various states across the US. According to census.gov, the 2007 estimated total population of each of these Osage Counties and which state they are located in are listed alphabetically as follows:# Osage County, Kansas: 16,459 # Osage County, Missouri: 13,393 # Osage County, Oklahoma: 45,523
That depends entirely on which Graham County you are requesting information about. There are three Graham Counties in various states across the US. According to census.gov, the 2007 estimated total population of each of these Graham Counties and which state they are located in are listed alphabetically as follows:# Graham County, Arizona: 34,769 # Graham County, Kansas: 2,607 # Graham County, North Carolina: 7,858
That depends entirely on which Harris County you are requesting information about. There are two Harris Counties in various states across the US. According to census.gov, the 2007 estimated total population of each of these Harris Counties and which state they are located in are listed alphabetically as follows:# Harris County, Georgia: 29,073 # Harris County, Texas: 3,935,855