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Marion County, OH Demographics

Marion County, OH is the 37th most populous of 88 counties in Ohio, with 65,359 residents across 404 square miles. That is about 162 people per square mile.

At the 2020 census

Population 65,359
Land area 404 sq mi
Density 162 / sq mi

Data: 2020 Census · American Community Survey 2024

How Marion 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: Marion County, OH

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

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

Census tracts in Marion County, OH

Name Population Sq mi Per sq mi
Census Tract 105 5,335 65.0 82
Census Tract 101 5,294 95.3 56
Census Tract 102.01 5,222 93.6 56
Census Tract 102.02 4,975 2.1 2,403
Census Tract 104 4,949 16.3 303
Census Tract 103 4,902 116.7 42
Census Tract 6 4,648 2.2 2,107
Census Tract 9 4,254 1.8 2,379
Census Tract 4 3,674 2.5 1,450
Census Tract 10 3,155 2.7 1,173
Census Tract 2 2,958 0.9 3,238
Census Tract 7 2,675 0.5 5,536
Census Tract 5.01 2,644 0.4 6,798
Census Tract 5.02 2,600 0.6 4,438
Census Tract 11 2,403 1.6 1,479
Census Tract 8 2,400 0.5 4,928
Census Tract 3 2,118 0.7 2,899
Census Tract 1 1,153 0.3 3,424

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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 →