Editing Crystal Lake, Illinois (section)

===2010 census===
As of the [[2010 United States Census|2010 Census]],<ref>{{cite web |url=https://factfinder.census.gov/bkmk/table/1.0/en/DEC/10_DP/DPDP1/1600000US1717887 |title=Profile of General Population and Housing Characteristics: 2010 |publisher=United States Census Bureau |access-date=2017-10-09 |archive-url=https://archive.today/20200213100141/https://factfinder.census.gov/bkmk/table/1.0/en/DEC/10_DP/DPDP1/1600000US1717887 |archive-date=2020-02-13 |url-status=dead }}</ref> there were 40,743 people, 14,421 households, and 10,551 families living in the city. The population density was 2,220/sq mi (857/km{{sup|2}}).<ref name="Quickfacts.census.gov">{{cite web |url=http://quickfacts.census.gov/qfd/states/17/1717887.html |title=Crystal Lake (city) QuickFacts from the US Census Bureau |publisher=Quickfacts.census.gov |access-date=2015-03-30 |archive-url=https://web.archive.org/web/20150417205656/http://quickfacts.census.gov/qfd/states/17/1717887.html |archive-date=2015-04-17 |url-status=dead }}</ref> There were 15,176 total housing units and 22% of all housing units were in multi-unit structures. The racial makeup of the city was 90.2% [[White Americans|White]], 1.0% [[African Americans|Black or African American]], 0.4% [[Native Americans in the United States|Native American]], 2.5% [[Asian Americans|Asian]], <0.01% [[Pacific Islander]], 4.1% from [[Race and ethnicity in the United States#Members of other races|other races]], and 1.8% from [[Multiracial Americans|two or more races]]. [[Hispanic and Latino Americans|Hispanic]] or [[Hispanic and Latino Americans|Latino]] of any race were 11.7% of the population.

39.2% of the households included children under 18, 58.9% were married couples living together, 10.1% had a female householder with no husband present, and 26.8% were non-families. 22.1% of all households were made up of individuals living alone, and 20.3% had someone at least 65 years old living alone. The average household size was 2.81 and the average family size was 3.31.

In the city, the population was spread out, with 28.1% under the age of 18, 8.% from 18 to 24, 26.2% from 25 to 44, 27.7% from 45 to 64, and 10.0% who were 65 years of age or older. The median age was 37 years. For every 100 females, there were 97.6 males.

The median income for a household in the city was $78,311, and the median income for a family was $91,870. Males had a median income of $61,982 versus $44,288 for females. The median income for the city was $36,405. About 5.2% of families and 6.2% of the population were below the poverty line, including 9.1% of those under age 18 and 5.3% of those age 65 or over.<ref name="Factfinder2.census.gov">{{cite web|url=https://www.census.gov |title=U.S. Census website |publisher=[[United States Census Bureau]] |date=2010-10-05 |access-date=2015-03-30}}</ref>