DeKalb County vs Gwinnett County

Two neighbouring counties in Georgia, compared on population, size, income and housing. They share 23 mi of border.

Both outlines are drawn at true relative size. Gwinnett County spans about 45.6 km at its widest.

Side by side

DeKalb County, Georgia and Gwinnett County, Georgia on shared measures. The middle column is the difference, computed from the two figures either side of it.
MeasureDeKalb CountyDifferenceGwinnett County
Population774,394-23.9%1,018,099
Change since 20201.3%-4.9 pp6.2%
Land area267.7 sq mi-37.9%431.1 sq mi
Population density2,893 per sq mi+22.5%2,361 per sq mi
Median household income$80,644-8.2%$87,890
Median home value$357,800-6.1%$380,900
Median age36.4+1.1%36.0
Households287,239-12.2%327,043
Housing units330,830-3.0%340,962

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026; US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. The difference column is computed here: the first county's figure against the second, expressed as a percentage of the second. The change-since-2020 row is the exception: two growth rates differ in percentage points (pp), not percent. Retrieved 30 August 2026.

What the numbers say

  • Gwinnett County holds about 1.3 times the population of DeKalb County: 1,018,099 against 774,394.
  • Gwinnett County covers more ground, at 431.1 square miles against 267.7.
  • DeKalb County is the more crowded of the two, at 2,893 people per square mile against 2,361.
  • Median household income is higher in Gwinnett County, by 7,246 dollars a year.
  • Since 2020, DeKalb County has grown by 1.3% and Gwinnett County has grown by 6.2%.
  • They share 23 mi of common border, which the Census Bureau publishes in its county adjacency file and which almost no other county reference presents.

Full pages

Want a different pair? Compare any two of the 3,144 US counties.

Rebuilt from source data 30 August 2026. How these figures are produced.