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Mercer County, OH Demographics

Mercer County, OH is the 58th most populous of 88 counties in Ohio, with 42,528 residents across 462 square miles. That is about 92 people per square mile.

At the 2020 census

Population 42,528
Land area 462 sq mi
Density 92 / sq mi

Data: 2020 Census · American Community Survey 2024

How Mercer 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: Mercer County, OH

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

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

Census tracts in Mercer County, OH

Name Population Sq mi Per sq mi
Census Tract 9679 7,333 77.0 95
Census Tract 9677 6,453 30.2 214
Census Tract 9675 5,650 10.3 551
Census Tract 9680 5,076 82.8 61
Census Tract 9674 4,857 9.1 534
Census Tract 9673 4,383 137.9 32
Census Tract 9672 3,662 92.4 40
Census Tract 9676 2,929 8.1 360
Census Tract 9678 2,185 14.8 148

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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 →