All counties →

Clark County, IL Demographics

Clark County, IL is the 71st most populous of 102 counties in Illinois, with 15,455 residents across 501 square miles. That is about 31 people per square mile.

At the 2020 census

Population 15,455
Land area 501 sq mi
Density 31 / sq mi

Data: 2020 Census · American Community Survey 2024

How Clark County compares to the US

We're computing this county's comparison table — check back shortly. Population, land area, and density above are already exact.

Central Location: Clark County, IL

Measured from the county's main population center using 2020 census blocks.

We're computing the drive-time and radius areas around Clark County, IL — check back shortly. Meanwhile you can drop a pin anywhere in the radius tool.

Census tracts in Clark County, IL

Name Population Sq mi Per sq mi
Census Tract 603 4,850 56.5 86
Census Tract 601 4,696 285.2 16
Census Tract 602 4,312 10.8 398
Census Tract 604 1,597 148.9 11

Related places

About this page

This page shows demographics for a US county from the 2020 census and the American Community Survey: population, land area, density, urban share, and how the county compares to national averages for income, housing, age, and more.

Counties subdivide into census tracts, listed below with their populations. The drive-time and radius tables measure the population around the county's main population center.

Read how BlockAtlas computes population within an area →