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zipcodes.pro — ZIP/94528

94528

ZIP 94528 is Diablo, California, in Contra Costa County; area code 925; Pacific time.

Type
Standard
Time zone
America/Los_Angeles
County
Contra Costa
Population
1,049
Coordinates
37.8415, -121.9582
☼ Live from 94528 — Diablo, CA

Weather right now

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Local time: —

Where 94528 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 94528
  • 🔢 Type 94528 into a pocket calculator and turn it upside down: BZShG — not quite a word, sorry.
  • ➕ As a number, 94,528 = 2 × 2 × 2 × 2 × 2 × 2 × 7 × 211. Its digits add up to 28, a total 1,520 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10111000101000000
  • 🏠 Its numerical neighbours: 94527 (Concord, CA, 8 mi away) and 94529 (Concord, CA, 10 mi away).
  • 🔄 Backwards, 94528 becomes 82549, which is not a ZIP code at all.
  • 👥 52 other ZIP codes are made of exactly the same digits (24589, 24598, 24859, 24895, 24985, 25849, …). The farthest-flung twin is 28594 in Emerald Isle, NC, 2,491 miles away.
  • 🧭 Farther south than 59% of all ZIP codes, and farther west than 95%.
  • 🎯1,262 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 94528 and you would come out at 37.84°S, 58.04°E — 999 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 47m of daylight. Shortest: 9h 32m.
  • 📏 At 1.2 square miles of land, 94528 is bigger than 9% of ZIP codes — about 559 football fields.
🌙 The sky over 94528 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population1,049This ZIP1,049
Households424This ZIP424
Housing units463This ZIP463
Median age43.0This ZIP43.0California37.9US 38.9
Median household income$207,500This ZIP$207,500California$99,122US $80,734
Median home value$2,000,000+This ZIP$2,000,000+California$734,700US $332,700
Bachelor's degree or higher79.8%This ZIP79.8%
Mean commute41.8 minThis ZIP41.8 min
Population density909.0 / sq miThis ZIP909.0 / sq mi

Business and tax activity

Business establishments22This ZIP22
Employees170This ZIP170
Annual payroll$13,196,000This ZIP$13,196,000

Land area

Land area1.15 sq miThis ZIP1.15 sq mi
Water area0.00 sq mi

Other place names in 94528

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

ZIP codes near 94528

ZIPCityDistance
94526 Danville, CA 2.3 mi
94507 Alamo, CA 2.8 mi
94506 Danville, CA 3.9 mi
94570 Moraga, CA 4.4 mi
94517 Clayton, CA 4.9 mi
94583 San Ramon, CA 5.1 mi
94596 Walnut Creek, CA 5.4 mi
94582 San Ramon, CA 5.8 mi
94598 Walnut Creek, CA 6.1 mi
94588 Pleasanton, CA 6.2 mi

Find every ZIP code within 10 miles of 94528 →

Questions about this ZIP code

Where is ZIP code 94528?

94528 is in Diablo, California, in Contra Costa County, part of the San Francisco-Oakland-Fremont, CA metropolitan area. Its published point location is 37.8415, -121.9582.

What county is 94528 in?

94528 lies in Contra Costa County.

What area code is 94528?

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

What time zone is 94528 in?

94528 uses America/Los_Angeles.

How many people live in 94528?

About 1,049 people live in ZIP code 94528, in 424 households, at 909.0 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 94528?

$207,500 a year, against $99,122 across California.

What ZIP codes are near 94528?

The closest are 94526 (2.3 mi), 94507 (2.8 mi), 94506 (3.9 mi), 94570 (4.4 mi) and 94517 (4.9 mi).

Is 94528 a PO Box ZIP code?

94528 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “94528 ZIP Code — Diablo, California (Contra Costa County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/94528

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