According to the 2000 census, the county has a total area of 376.15 square miles (974.2 km2), of which 357.04 square miles (924.7 km2) (or 94.92%) is land and 19.11 square miles (49.5 km2) (or 5.08%) is water. Carver is one of seven southern Minnesota counties with no forest soils; only prairie ecosystems of savannas and prairies can be found in Carver County. It is also one of 17 Minnesota counties where savanna soils dominate. Native vegetation based on NRCS soils information shows:
There were 24,356 households out of which 45.20% had children under the age of 18 living with them, 66.40% were married couples living together, 7.30% had a female householder with no husband present, and 22.90% were non-families. 18.10% of all households were made up of individuals and 6.10% had someone living alone who was 65 years of age or older. The average household size was 2.84 and the average family size was 3.26.
In the county the population was spread out with 31.50% under the age of 18, 6.90% from 18 to 24, 34.70% from 25 to 44, 19.50% from 45 to 64, and 7.50% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 100.00 males. For every 100 females age 18 and over, there were 98.00 males.
The median income for a household in the county was $65,540, and the median income for a family was $73,577 (these figures had risen to $78,035 and $89,100 respectively as of a 2007 estimate). Males had a median income of $47,271 versus $32,107 for females. The per capita income for the county was $28,486. About 2.30% of families and 3.50% of the population were below the poverty line, including 3.60% of those under age 18 and 6.90% of those age 65 or over.
In recent years, average temperatures in the county seat of Chaska have ranged from a low of 4 °F (−16 °C) in January to a high of 81 °F (27 °C) in July, although a record low of −41 °F (−41 °C) was recorded in January 1970 and a record high of 105 °F (41 °C) was recorded in July 1988. Average monthly precipitation ranged from 0.66 inches (17 mm) in February to 5.05 inches (128 mm) in August.