DeKalb, Illinois demographics

DeKalb, IL demographics: median age 26.1; 33.7% of adults 25+ hold a bachelor’s degree. Age, race, households, languages and education, ACS 2020–2024 with margins of error.

ACS 2020–2024 · DeKalb city, Illinois · Incorporated city · GEOID 1719161. The survey estimates a population of 40,443 for its five-year window. This is separate from the annual July 2025 population estimate on the city overview.

Median age in DeKalb is 26.1 years, with a 90% margin of error of 1.0 years. There are 16,388 households (±497). Age and household distributions show how these totals are composed; they do not establish which neighborhood suits a particular person.

Every count and share is an estimate. “±” is a 90% margin of error (MOE); pp means percentage points. Derived shares use the category count divided by the named universe. Aggregated category MOEs and percentage MOEs are approximate. A margin larger than half its estimate is flagged as low precision. Blank source uncertainty is shown as unavailable, never zero.

Age distribution and sex

City, state and U.S. estimates · ACS 2020–2024
Measure / survey universe	City estimate ± MOE	State estimate ± MOE	U.S. estimate ± MOE
Median age Total population · years	26.1 ±1.0	39.0 ±0.1	38.9 ±0.1

Age groups · B01001 · ACS 2020–2024 Total population: 40,443
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
Under 18	7,595 ±664	18.8% ±1.6 pp	21.8%	22.0%
18–34	17,613 ±1,222	43.6% ±3.0 pp	22.7%	22.8%
35–64	10,763 ±703	26.6% ±1.7 pp	38.5%	38.0%
65 and older	4,472 ±439	11.1% ±1.1 pp	17.0%	17.2%

Sex categories as published by ACS · B01001 · ACS 2020–2024 Total population: 40,443
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
Male	19,855 ±485	49.1% ±1.2 pp	49.4%	49.5%
Female	20,588 ±483	50.9% ±1.2 pp	50.6%	50.5%

The age groups are mutually exclusive and cover the entire population. The sex categories follow this ACS table’s published classification; they are not a survey of gender identity.

Race and Hispanic origin

Race · B02001 · ACS 2020–2024 Total population: 40,443
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
White alone	24,488 ±856	60.5% ±2.1 pp	61.0%	61.0%
Black or African American alone	5,701 ±607	14.1% ±1.5 pp	13.6%	12.2%
American Indian and Alaska Native alone	493 ±328 · low precision	1.2% ±0.8 pp · low precision	0.6%	0.9%
Asian alone	1,675 ±399	4.1% ±1.0 pp	6.0%	6.0%
Native Hawaiian and Other Pacific Islander alone	0 ±27 · low precision	0.0% ±0.1 pp · low precision	0.0%	0.2%
Some other race alone	2,450 ±606	6.1% ±1.5 pp	7.9%	7.1%
Two or more races	5,636 ±785	13.9% ±1.9 pp	10.9%	12.6%

Hispanic or Latino origin · B03003 · ACS 2020–2024 Total population: 40,443
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
Not Hispanic or Latino	32,385 ±714	80.1% ±1.7 pp	81.2%	80.7%
Hispanic or Latino	8,058 ±673	19.9% ±1.7 pp	18.8%	19.3%

Hispanic origin and race are separate questions. People of Hispanic or Latino origin may be of any race and appear in both tables. Do not add the Hispanic share to race shares. Race alone and two-or-more-race groups are the mutually exclusive categories of the race table.

Household types, children and living alone

Household types · B11001 · ACS 2020–2024 Households: 16,388
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
Married-couple family	4,310 ±432	26.3% ±2.5 pp	45.3%	46.9%
Other family: male householder, no spouse present	836 ±266	5.1% ±1.6 pp	4.9%	5.1%
Other family: female householder, no spouse present	2,609 ±387	15.9% ±2.3 pp	11.9%	12.2%
Nonfamily: householder living alone	6,284 ±679	38.3% ±4.0 pp	31.2%	28.7%
Nonfamily: householder not living alone	2,349 ±489	14.3% ±3.0 pp	6.7%	7.0%

Households with children · B11005 · ACS 2020–2024 Households: 16,388
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
Households with people under 18	4,193 ±390	25.6% ±2.2 pp	28.6%	29.5%
Households without people under 18	12,195 ±709	74.4% ±3.7 pp	71.4%	70.5%

Household size · B11016 · ACS 2020–2024 Households: 16,388
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
One-person nonfamily households	6,284 ±679	38.3% ±4.0 pp	31.2%	28.7%
Two-person households	5,511 ±711	33.6% ±4.2 pp	32.3%	33.8%
Three-person households	1,719 ±337	10.5% ±2.0 pp	14.7%	15.3%
Four-person households	1,622 ±318	9.9% ±1.9 pp	12.6%	12.6%
Five-person households	840 ±268	5.1% ±1.6 pp	5.8%	5.9%
Six-person households	273 ±92	1.7% ±0.6 pp	2.1%	2.2%
Seven or more people	139 ±82 · low precision	0.8% ±0.5 pp · low precision	1.3%	1.4%

A family household contains related people under the Census definition. A nonfamily household can contain one person or unrelated people sharing a home. Households with children can also appear in the household-type and size tables, so those tables must not be added together. Household estimates exclude people living in group quarters from the household universe.

Nativity and languages spoken at home

Nativity · B05002 · ACS 2020–2024 Total population: 40,443
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
Native	36,751 ±688	90.9% ±1.6 pp	85.3%	85.9%
Foreign born	3,692 ±637	9.1% ±1.6 pp	14.7%	14.1%

Language spoken at home · C16001 · ACS 2020–2024 Population age 5 and older: 38,557
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
English only	31,678 ±876	82.2% ±2.1 pp	76.0%	77.7%
Spanish	4,561 ±547	11.8% ±1.4 pp	14.0%	13.6%
French, Haitian, or Cajun	50 ±41 · low precision	0.1% ±0.1 pp · low precision	0.3%	0.7%
German or other West Germanic	42 ±44 · low precision	0.1% ±0.1 pp · low precision	0.3%	0.5%
Russian, Polish, or other Slavic	247 ±124 · low precision	0.6% ±0.3 pp · low precision	2.5%	0.7%
Other Indo-European	609 ±320 · low precision	1.6% ±0.8 pp · low precision	2.6%	2.0%
Korean	0 ±27 · low precision	0.0% ±0.1 pp · low precision	0.3%	0.3%
Chinese, including Mandarin and Cantonese	275 ±224 · low precision	0.7% ±0.6 pp · low precision	0.9%	1.1%
Vietnamese	47 ±57 · low precision	0.1% ±0.1 pp · low precision	0.2%	0.5%
Tagalog, including Filipino	228 ±166 · low precision	0.6% ±0.4 pp · low precision	0.7%	0.6%
Other Asian and Pacific Island	361 ±270 · low precision	0.9% ±0.7 pp · low precision	1.0%	1.1%
Arabic	287 ±169 · low precision	0.7% ±0.4 pp · low precision	0.6%	0.5%
Other and unspecified	172 ±146 · low precision	0.4% ±0.4 pp · low precision	0.6%	0.8%

Foreign born means not a U.S. citizen at birth; it includes naturalized citizens. Language categories describe speech at home among people age five and older. A language other than English at home does not establish that someone cannot speak English. This city page uses the published C16001 summary categories because the more detailed B16001 table does not provide these city records in this release.

Educational attainment

Highest completed education · B15003 · ACS 2020–2024 Population age 25 and older: 20,800
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
Less than high school graduate	2,478 ±503	11.9% ±2.4 pp	9.5%	10.4%
High school graduate or equivalency	5,129 ±532	24.7% ±2.4 pp	25.1%	26.0%
Some college, no degree	4,370 ±525	21.0% ±2.4 pp	19.2%	19.1%
Associate’s degree	1,807 ±323	8.7% ±1.5 pp	8.3%	8.8%
Bachelor’s degree	4,079 ±586	19.6% ±2.7 pp	22.6%	21.6%
Graduate or professional degree	2,937 ±438	14.1% ±2.0 pp	15.3%	14.1%

The denominator excludes residents under 25. Each person is counted in the highest attainment category they completed. This table does not measure the quality of local schools or the education level of every current student.

Residence one year earlier

Geographic mobility · B07003 · ACS 2020–2024 Population age 1 and older: 40,075
Category	Count ± MOE	Share ± MOE (pp)	Illinois	U.S.
Same house	29,738 ±1,289	74.2% ±3.2 pp	88.9%	87.7%
Moved within same county	4,294 ±785	10.7% ±2.0 pp	6.4%	6.3%
Moved from a different county in the same state	4,623 ±788	11.5% ±2.0 pp	2.4%	3.1%
Moved from a different state	947 ±320	2.4% ±0.8 pp	1.6%	2.3%
Moved from abroad	473 ±233	1.2% ±0.6 pp	0.6%	0.6%

These are respondents’ residence patterns one year before their survey response, pooled across the five-year window. They are not a net migration count for 2025. A person can move to a different house within the same city or county; moves within the same county should not automatically be interpreted as new arrivals to the city.

Health insurance, internet access and veterans

7.2% of DeKalb residents (±1.5 percentage points) had no health insurance coverage when surveyed, compared with 6.9% in Illinois and 8.4% nationally. 90.8% of households subscribe to broadband of any type, including cellular data plans. A subscription is not the same as available service: the FCC National Broadband Map shows providers at a specific address.

City, state and U.S. shares · ACS 2020–2024
Measure	DeKalb	Illinois	U.S.	Compared with Illinois
People without health insurance Civilian noninstitutionalized population	7.2% ±1.5 pp	6.9%	8.4%	Not statistically different
Households with a broadband subscription Households	90.8% ±2.1 pp	90.8%	91.0%	Not statistically different
Veterans Civilian population age 18 and older	4.2% ±1.0 pp	4.8%	6.2%	Not statistically different

Reading and reusing the estimates

The Census table links above lead to the original detailed tables. Counts, source universes and uncertainty are retained in the source observation download for DeKalb . Compare these figures with the same survey window; do not compare one city’s five-year estimate with another city’s annual estimate as though they measured the same period. For methods, see uncertainty and denominator calculations.

Read DeKalb housing and cost context or return to the city profile.