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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/94021

94021

ZIP 94021 is Loma Mar, California, in San Mateo County; area code 650; Pacific time.

Type
Standard
Time zone
America/Los_Angeles
County
San Mateo
Population
321
Coordinates
37.2503, -122.2496
☼ Live from 94021 — Loma Mar, CA

Weather right now

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NEXRAD radar
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Local time: —

Where 94021 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 94021
  • 🔢 Type 94021 into a pocket calculator and turn it upside down: IZOhG — not quite a word, sorry.
  • ➕ As a number, 94,021 = 167 × 563. Its digits add up to 16, a total 1,922 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10110111101000101
  • 🏠 Its numerical neighbours: 94020 (La Honda, CA, 2 mi away) and 94022 (Los Altos, CA, 9 mi away).
  • 🔄 Backwards, 94021 becomes 12049, which is not a ZIP code at all.
  • 👥 56 other ZIP codes are made of exactly the same digits (02149, 02914, 04219, 04291, 04912, 04921, …). The farthest-flung twin is 09142 in APO AE, a military post office, 5,808 miles away.
  • 🧭 Farther south than 63% of all ZIP codes, and farther west than 96%.
  • 🎯1,288 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 94021 and you would come out at 37.25°S, 57.75°E — 1,042 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 44m of daylight. Shortest: 9h 36m.
  • 📏 At 11.0 square miles of land, 94021 is bigger than 28% of ZIP codes — room for about 8.3 Central Parks.
🌙 The sky over 94021 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population321This ZIP321
Households128This ZIP128
Housing units140This ZIP140
Median age46.8This ZIP46.8California37.9US 38.9
Median household income$250,000+This ZIP$250,000+California$99,122US $80,734
Median home value$1,073,100This ZIP$1,073,100California$734,700US $332,700
Bachelor's degree or higher71.0%This ZIP71.0%
Population density29.3 / sq miThis ZIP29.3 / sq mi

Business and tax activity

Business establishments8This ZIP8
Employees42This ZIP42
Annual payroll$2,797,000This ZIP$2,797,000

Land area

Land area10.97 sq miThis ZIP10.97 sq mi
Water area0.00 sq mi

Other place names in 94021

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

ZIP codes near 94021

ZIPCityDistance
94060 Pescadero, CA 1.3 mi
94020 La Honda, CA 2.0 mi
94074 San Gregorio, CA 7.6 mi
95006 Boulder Creek, CA 7.8 mi
94028 Portola Valley, CA 8.8 mi
94022 Los Altos, CA 9.3 mi
95014 Cupertino, CA 10.1 mi
94026 Menlo Park, CA 10.2 mi
94064 Redwood City, CA 10.2 mi
95017 Davenport, CA 10.8 mi

Find every ZIP code within 10 miles of 94021 →

Questions about this ZIP code

Where is ZIP code 94021?

94021 is in Loma Mar, California, in San Mateo County, part of the San Francisco-Oakland-Fremont, CA metropolitan area. Its published point location is 37.2503, -122.2496.

What county is 94021 in?

94021 lies in San Mateo County.

What area code is 94021?

Loma Mar uses area code 650, from NANPA's telephone records.

What time zone is 94021 in?

94021 uses America/Los_Angeles.

How many people live in 94021?

About 321 people live in ZIP code 94021, in 128 households, at 29.3 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 94021?

$250,000+ a year, against $99,122 across California.

What ZIP codes are near 94021?

The closest are 94060 (1.3 mi), 94020 (2 mi), 94074 (7.6 mi), 95006 (7.8 mi) and 94028 (8.8 mi).

Is 94021 a PO Box ZIP code?

94021 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “94021 ZIP Code — Loma Mar, California (San Mateo County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/94021

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