Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — ZIP/21230

21230

ZIP 21230 is in Baltimore, Maryland, in Baltimore City; area codes 410, 443 and 667; Eastern time. Baltimore has 42 ZIP codes in all.

Type
Standard
Time zone
America/New_York
Population
32,977
Coordinates
39.2681, -76.6267
☼ Live from 21230 — Baltimore, MD

Weather right now

Asking the National Weather Service…

NEXRAD radar
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Local time: —

Where 21230 is

Approximate ZIP boundary (Census ZCTA 2020). ZIP codes are mail routes, not areas, so the shape shown is the Census tabulation area that approximates it.

★ Weird and wonderful facts about 21230
  • 🔢 Type 21230 into a pocket calculator and turn it upside down: OEZIZ — not quite a word, sorry.
  • ➕ As a number, 21,230 = 2 × 5 × 11 × 193. Its digits add up to 8, a total 251 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101001011101110
  • 🏠 Its numerical neighbours: 21229 (Baltimore, MD, 4 mi away) and 21231 (Baltimore, MD, 2 mi away).
  • 🔄 Backwards, 21230 becomes 03212, which is not a ZIP code at all.
  • 👥 33 other ZIP codes are made of exactly the same digits (01223, 02123, 02132, 03221, 12023, 12032, …). The farthest-flung twin is 32102 in Astor, FL, 753 miles away.
  • 🧭 Farther north than 51% of all ZIP codes, and farther east than 83%.
  • 🎯1,167 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21230 and you would come out at 39.27°S, 103.37°E — 863 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 56m of daylight. Shortest: 9h 24m.
  • 📏 At 6.3 square miles of land, 21230 is bigger than 21% of ZIP codes — room for about 4.8 Central Parks.
🌙 The sky over 21230 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population32,977This ZIP32,977
Households16,496This ZIP16,496
Housing units18,478This ZIP18,478
Median age33.9This ZIP33.9Maryland39.4US 38.9
Median household income$91,842This ZIP$91,842Maryland$103,678US $80,734
Median home value$330,100This ZIP$330,100Maryland$419,900US $332,700
Median gross rent$1,717This ZIP$1,717Maryland$1,705US $1,413
Bachelor's degree or higher58.8%This ZIP58.8%
Mean commute26.4 minThis ZIP26.4 min
Population density5,219.5 / sq miThis ZIP5,219.5 / sq mi

Business and tax activity

Business establishments1,201This ZIP1,201
Employees26,828This ZIP26,828
Annual payroll$2,083,111,000This ZIP$2,083,111,000
Tax returns filed18,580This ZIP18,580
Total adjusted gross income$1,810,592,000This ZIP$1,810,592,000

Land area

Land area6.32 sq miThis ZIP6.32 sq mi
Water area2.22 sq miThis ZIP2.22 sq mi

Other place names in 21230

Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.

ZIP codes near 21230

ZIPCityDistance
21203 Baltimore, MD 1.2 mi
21235 Baltimore, MD 1.2 mi
21241 Baltimore, MD 1.2 mi
21263 Baltimore, MD 1.2 mi
21264 Baltimore, MD 1.2 mi
21270 Baltimore, MD 1.2 mi
21273 Baltimore, MD 1.2 mi
21275 Baltimore, MD 1.2 mi
21278 Baltimore, MD 1.2 mi
21279 Baltimore, MD 1.2 mi

Find every ZIP code within 10 miles of 21230 →

Questions about this ZIP code

Where is ZIP code 21230?

21230 is in Baltimore, Maryland, in Baltimore city, part of the Baltimore-Columbia-Towson, MD metropolitan area. Its published point location is 39.2681, -76.6267.

What county is 21230 in?

21230 lies in Baltimore city.

What area code is 21230?

Baltimore uses area codes 410, 443 and 667, from NANPA's telephone records.

What time zone is 21230 in?

21230 uses America/New_York.

How many people live in 21230?

About 32,977 people live in ZIP code 21230, in 16,496 households, at 5,219.5 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What is the median household income in 21230?

$91,842 a year, against $103,678 across Maryland.

What ZIP codes are near 21230?

The closest are 21203 (1.2 mi), 21235 (1.2 mi), 21241 (1.2 mi), 21263 (1.2 mi) and 21264 (1.2 mi).

Is 21230 a PO Box ZIP code?

21230 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21230 ZIP Code — Baltimore, Maryland (Baltimore City).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21230

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