MO · GEOID 29103

Knox County area

Knox County, Missouri covers 506.8 square miles: 504 square miles of land and 2.8 square miles of water.

Official Census measurements2026 Gazetteer · retrieved September 27, 2026
Land area504 mi²
Water area2.8 mi²
Total area506.8 mi²
National land rank#2062

County outline

Generalized outline of Knox County, Missouri
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Knox County is located

Knox County highlighted on a map of all U.S. county equivalents. About the maps

Area breakdown

Land accounts for 99.4% of Knox County’s measured area and water for 0.6%. Its combined area converts to 1,312.7 square kilometers or approximately 324,371 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land504.011,305.38322,566.4
Water2.827.3041,804.8
Total506.831,312.684324,371.2

How Knox County compares

By original Census land area, Knox County ranks #81 of 115 in Missouri and #2062 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.851 times the Missouri county-equivalent median of 592 square miles. It accounts for 0.7% of the combined county land area in the state.

See the complete Missouri ranking · What counts as a county equivalent?

What stands out about Knox County?

Knox County has more land than 1,160 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Knox County504 mi²
Missouri median592 mi²
National median604.5 mi²

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Knox County at #2,150 nationally by total area, 88 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 0.6%, compared with a national county-equivalent median of 1.2% — 0.6 percentage points lower. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Knox County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2061Athens County, Ohio504.1Compare
#2062Knox County, Missouri504This county
#2063Muskegon County, Michigan503.9Compare

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.

Representative coordinates

The Census internal point is 40.136856, -92.146835. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.

Source and precision

U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 1,305,380,278 m²; AWATER: 7,303,438 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How many acres of land are in Knox County?

The land measurement converts to approximately 322,566 acres. Including water, total area is approximately 324,371 acres. One square mile equals 640 acres.

Why might another source show a different area?

Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.

Can this establish a property boundary?

No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.

Cite this county

Download the complete CSV or JSON dataset