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zipcodes.pro — ZIP/94521

94521

ZIP 94521 is in Concord, California, in Contra Costa County; area code 925; Pacific time. Concord has 8 ZIP codes in all.

Type
Standard
Time zone
America/Los_Angeles
County
Contra Costa
Population
41,909
Coordinates
37.9529, -121.9697
☼ Live from 94521 — Concord, CA

Weather right now

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Local time: —

Where 94521 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 94521
  • 🔢 Type 94521 into a pocket calculator and turn it upside down: IZShG — not quite a word, sorry.
  • ➕ As a number, 94,521 = 3 × 7 × 7 × 643. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10111000100111001
  • 🏠 Its numerical neighbours: 94520 (Concord, CA, 5 mi away) and 94522 (Concord, CA, 4 mi away).
  • 🔄 Backwards, 94521 becomes 12549 — and that is a real ZIP code: Montgomery, NY, 2,515 miles away.
  • 👥 47 other ZIP codes are made of exactly the same digits (12459, 12495, 12549, 12594, 12945, 14529, …). The farthest-flung twin is 12594 in Wingdale, NY, 2,548 miles away.
  • 🧭 Farther south than 58% of all ZIP codes, and farther west than 95%.
  • 🎯1,261 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 94521 and you would come out at 37.95°S, 58.03°E — 993 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 48m of daylight. Shortest: 9h 32m.
  • 📏 At 9.7 square miles of land, 94521 is bigger than 27% of ZIP codes — room for about 7.4 Central Parks.
🌙 The sky over 94521 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population41,909This ZIP41,909
Households15,938This ZIP15,938
Housing units16,451This ZIP16,451
Median age42.9This ZIP42.9California37.9US 38.9
Median household income$125,899This ZIP$125,899California$99,122US $80,734
Median home value$853,200This ZIP$853,200California$734,700US $332,700
Median gross rent$2,404This ZIP$2,404California$2,036US $1,413
Bachelor's degree or higher44.6%This ZIP44.6%
Mean commute34.0 minThis ZIP34.0 min
Population density4,328.1 / sq miThis ZIP4,328.1 / sq mi

Business and tax activity

Business establishments655This ZIP655
Employees5,659This ZIP5,659
Annual payroll$261,321,000This ZIP$261,321,000
Tax returns filed20,440This ZIP20,440
Total adjusted gross income$2,320,827,000This ZIP$2,320,827,000

Land area

Land area9.68 sq miThis ZIP9.68 sq mi
Water area0.00 sq mi

Other place names in 94521

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

ZIP codes near 94521

ZIPCityDistance
94527 Concord, CA 0.6 mi
94518 Concord, CA 2.9 mi
94519 Concord, CA 3.4 mi
94598 Walnut Creek, CA 3.5 mi
94522 Concord, CA 3.8 mi
94524 Concord, CA 3.8 mi
94529 Concord, CA 3.8 mi
94565 Pittsburg, CA 4.5 mi
94520 Concord, CA 4.5 mi
94596 Walnut Creek, CA 5.7 mi

Find every ZIP code within 10 miles of 94521 →

Questions about this ZIP code

Where is ZIP code 94521?

94521 is in Concord, California, in Contra Costa County, part of the San Francisco-Oakland-Fremont, CA metropolitan area. Its published point location is 37.9529, -121.9697.

What county is 94521 in?

94521 lies in Contra Costa County.

What area code is 94521?

Concord uses area code 925, from NANPA's telephone records.

What time zone is 94521 in?

94521 uses America/Los_Angeles.

How many people live in 94521?

About 41,909 people live in ZIP code 94521, in 15,938 households, at 4,328.1 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 94521?

$125,899 a year, against $99,122 across California.

What ZIP codes are near 94521?

The closest are 94527 (0.6 mi), 94518 (2.9 mi), 94519 (3.4 mi), 94598 (3.5 mi) and 94522 (3.8 mi).

Is 94521 a PO Box ZIP code?

94521 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “94521 ZIP Code — Concord, California (Contra Costa County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/94521

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