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zipcodes.pro — ZIP/02421

02421

ZIP 02421 is in Lexington, Massachusetts, in Middlesex County; area codes 781 and 339; Eastern time. Lexington has 2 ZIP codes; the other is 02420.

Type
Standard
Time zone
America/New_York
County
Middlesex
Population
18,080
Coordinates
42.4385, -71.2396
☼ Live from 02421 — Lexington, MA

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Where 02421 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 02421
  • 🔢 Type 02421 into a pocket calculator and turn it upside down: IZhZO — not quite a word, sorry.
  • ➕ As a number, 2,421 = 3 × 3 × 269. Its digits add up to 9, a total 375 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 100101110101
  • 🏠 Its numerical neighbours: 02420 (Lexington, MA, 2 mi away) and 02445 (Brookline, MA, 9 mi away).
  • 🔄 Backwards, 02421 becomes 12420 — and that is a real ZIP code: Cragsmoor, NY, 170 miles away.
  • 👥 43 other ZIP codes are made of exactly the same digits (01224, 01242, 02124, 02142, 02241, 04122, …). The farthest-flung twin is 42021 in Arlington, KY, 1,019 miles away.
  • 🧭 Farther north than 79% of all ZIP codes, and farther east than 96%.
  • 🎯1,428 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 02421 and you would come out at 42.44°S, 108.76°E — 822 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 18m of daylight. Shortest: 9h 04m.
  • 📏 At 9.6 square miles of land, 02421 is bigger than 26% of ZIP codes — room for about 7.3 Central Parks.
🌙 The sky over 02421 today
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🌋 Shake report
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Source: USGS.

People and housing

Population18,080This ZIP18,080
Households6,824This ZIP6,824
Housing units6,903This ZIP6,903
Median age48.2This ZIP48.2Massachusetts40.0US 38.9
Median household income$227,813This ZIP$227,813Massachusetts$103,960US $80,734
Median home value$1,205,700This ZIP$1,205,700Massachusetts$562,100US $332,700
Median gross rent$2,948This ZIP$2,948Massachusetts$1,762US $1,413
Bachelor's degree or higher83.2%This ZIP83.2%
Mean commute31.4 minThis ZIP31.4 min
Population density1,889.4 / sq miThis ZIP1,889.4 / sq mi

Business and tax activity

Business establishments582This ZIP582
Employees20,781This ZIP20,781
Annual payroll$3,470,654,000This ZIP$3,470,654,000
Tax returns filed8,580This ZIP8,580
Total adjusted gross income$2,908,436,000This ZIP$2,908,436,000

Land area

Land area9.57 sq miThis ZIP9.57 sq mi
Water area0.16 sq miThis ZIP0.16 sq mi

Other place names in 02421

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

ZIP codes near 02421

ZIPCityDistance
02420 Lexington, MA 1.8 mi
02451 Waltham, MA 2.6 mi
01731 Hanscom Afb, MA 2.9 mi
02452 Waltham, MA 3.1 mi
02475 Arlington Heights, MA 3.3 mi
02476 Arlington, MA 3.7 mi
01773 Lincoln, MA 3.7 mi
02478 Belmont, MA 4.3 mi
02474 Arlington, MA 4.4 mi
02479 Waverley, MA 4.6 mi

Find every ZIP code within 10 miles of 02421 →

Questions about this ZIP code

Where is ZIP code 02421?

02421 is in Lexington, Massachusetts, in Middlesex County, part of the Boston-Cambridge-Newton, MA-NH metropolitan area. Its published point location is 42.4385, -71.2396.

What county is 02421 in?

02421 lies in Middlesex County.

What area code is 02421?

Lexington uses area codes 781 and 339, from NANPA's telephone records.

What time zone is 02421 in?

02421 uses America/New_York.

How many people live in 02421?

About 18,080 people live in ZIP code 02421, in 6,824 households, at 1,889.4 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 02421?

$227,813 a year, against $103,960 across Massachusetts.

What ZIP codes are near 02421?

The closest are 02420 (1.8 mi), 02451 (2.6 mi), 01731 (2.9 mi), 02452 (3.1 mi) and 02475 (3.3 mi).

Is 02421 a PO Box ZIP code?

02421 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “02421 ZIP Code — Lexington, Massachusetts (Middlesex County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/02421

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