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Population per Square Mile in Illinois, by County

Population per Square Mile for every county in Illinois, ranked. The highest is Cook County at 5,484.2 and the lowest is Pope County at 10.1.

Illinois: 228.7 · United States: n/a · median county in Illinois: 44.8

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#County Population per Square Mile
1Cook County5,484.2
2DuPage County2,836.7
3Lake County1,609.8
4Kane County996.1
5Will County839.2
6Winnebago County552.2
7McHenry County518.0
8Kendall County429.9
9St. Clair County385.7
10Madison County369.3
11Rock Island County333.9
12Peoria County290.4
13Sangamon County224.5
14Champaign County209.6
15Tazewell County201.5
16Boone County189.6
17Macon County175.4
18DeKalb County159.5
19Williamson County159.1
20Kankakee County157.6
21McLean County145.0
22Grundy County127.3
23LaSalle County95.8
24Coles County92.0
25Franklin County91.3
26Jackson County90.9
27Monroe County90.9
28Vermilion County80.6
29Whiteside County80.3
30Clinton County78.0
31Stephenson County77.6
32Adams County75.7
33Woodford County72.6
34Effingham County72.1
35Knox County68.5
36Ogle County67.9
37Marion County64.6
38Jefferson County64.0
39Saline County61.1
40Henry County59.1
41Massac County58.5
42Morgan County58.0
43Jersey County57.6
44Randolph County52.2
45Macoupin County51.4
46Wabash County49.8
47Douglas County47.4
48Christian County47.3
49Lee County46.7
50Perry County46.7
51McDonough County45.7
52Logan County44.8
53Bond County44.0
54Richland County43.3
55Moultrie County42.9
56Crawford County41.7
57Union County41.1
58Lawrence County40.4
59Montgomery County39.7
60Johnson County38.9
61De Witt County38.7
62Menard County38.5
63Fulton County38.1
64Piatt County38.0
65Bureau County37.8
66Jo Daviess County36.4
67Carroll County35.0
68Putnam County35.0
69Livingston County34.1
70Cass County34.0
71Clark County30.4
72Warren County30.3
73Marshall County30.1
74Cumberland County29.9
75Fayette County29.8
76Clay County27.9
77Ford County27.6
78Mercer County27.6
79White County27.5
80Edwards County27.3
81Shelby County27.3
82Edgar County26.5
83Pulaski County25.2
84Washington County24.2
85Iroquois County23.7
86Mason County23.6
87Wayne County22.4
88Hancock County21.8
89Greene County21.5
90Alexander County20.7
91Brown County20.7
92Hardin County20.3
93Scott County19.7
94Jasper County18.6
95Stark County18.4
96Hamilton County18.2
97Pike County17.4
98Calhoun County17.1
99Henderson County16.3
100Schuyler County15.5
101Gallatin County14.9
102Pope County10.1

People divided by land area. Water is excluded, so lake and coastal counties are not unfairly diluted.

Source: ACS 2020-2024 5-Year Estimates, 2024.

Illinois ranks 14th of 52 states for population per square mile.

Population per Square Mile in other states

Other statistics for Illinois by county