Arnold, Missouri

Arnold population, 2020 to 2024

Arnold added 128 residents from July 2020 to July 2024, a change of +0.6%. In the latest year it moved by -66. Among 135 Missouri places of 5,000 or more, that growth ranks 78th; the median place changed by +1.2%. The median place of 5,000+ in Missouri has 12,239 people, so Arnold is 1.7 times that size.

Arnold covers 11.53 square miles of land, for 1,824 people per square mile of land. The median Missouri place of 5,000+ has 1,448, so Arnold is denser than the typical town.

What county Arnold is in

All of Arnold's residents live in Jefferson County, which had 231,888 residents in 2024. Arnold holds 9.1% of the county's population. The shaded shape is on the map above; dots mark the eight nearest places.

ZIP codes in Arnold

1 ZIP Code Tabulation Area (ZCTA) overlaps Arnold by at least 10% of the ZCTA's or the city's land: 63010. ZCTAs are Census approximations of USPS ZIP code delivery areas. The list comes from the 2020 ZCTA to place relationship file, so a city that annexed land after 2020 may reach into ZIP codes not listed here.

Where Arnold is

The Census internal point of Arnold is at 38.426000, -90.369300. Jefferson City, the capital, is 98.1 miles W in a straight line. The nearest larger place is Kirkwood, MO (29,348 people), 10.9 miles away. The nearest city of 100,000 or more is St. Louis, MO, 16.0 miles away.

Daylight in Arnold

At 38.43° N, Arnold gets about 14 h 51 min of daylight around the June solstice and 9 h 29 min around the December solstice, a swing of 5 h 22 min. Figures are sunrise to sunset from the SunCalc model for June 21 and December 21, 2026.

Places near Arnold

The eight nearest incorporated places of 1,000+ in Missouri, measured between internal points. The closest is Green Park, 6.9 miles away, with 2,682 people.