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/91901

91901

ZIP 91901 is in Alpine, California, in San Diego County; area codes 619 and 858; Pacific time. Alpine has 2 ZIP codes; the other is 91903.

Type
Standard
Time zone
America/Los_Angeles
County
San Diego
Population
18,197
Coordinates
32.8136, -116.7270
☼ Live from 91901 — Alpine, CA

Weather right now

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Local time: —

Where 91901 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 91901
  • 🔢 Type 91901 into a pocket calculator and turn it upside down: IOGIG — not quite a word, sorry.
  • ➕ As a number, 91,901 = 29 × 3169. Its digits add up to 20, a total 2,586 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10110011011111101
  • 🏠 Its numerical neighbours: 91899 (Alhambra, CA, 120 mi away) and 91902 (Bonita, CA, 19 mi away).
  • 🔄 Backwards, 91901 becomes 10919 — and that is a real ZIP code: Circleville, NY, 2,382 miles away.
  • 👥 13 other ZIP codes are made of exactly the same digits (01199, 10199, 10919, 19019, 19091, 19109, …). The farthest-flung twin is 01199 in Springfield, MA, 2,474 miles away.
  • 🧭 Farther south than 85% of all ZIP codes, and farther west than 89%.
  • 🎯1,118 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 91901 and you would come out at 32.81°S, 63.27°E — 944 miles from Port Louis, Mauritius, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 19m of daylight. Shortest: 9h 59m.
  • 📏 At 77.9 square miles of land, 91901 is bigger than 72% of ZIP codes — room for about 59 Central Parks.
🌙 The sky over 91901 today
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🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population18,197This ZIP18,197
Households6,344This ZIP6,344
Housing units6,591This ZIP6,591
Median age42.2This ZIP42.2California37.9US 38.9
Median household income$114,167This ZIP$114,167California$99,122US $80,734
Median home value$852,000This ZIP$852,000California$734,700US $332,700
Median gross rent$2,055This ZIP$2,055California$2,036US $1,413
Bachelor's degree or higher31.3%This ZIP31.3%
Mean commute32.2 minThis ZIP32.2 min
Population density233.7 / sq miThis ZIP233.7 / sq mi

Business and tax activity

Business establishments450This ZIP450
Employees4,802This ZIP4,802
Annual payroll$254,394,000This ZIP$254,394,000
Tax returns filed8,040This ZIP8,040
Total adjusted gross income$939,593,000This ZIP$939,593,000

Land area

Land area77.87 sq miThis ZIP77.87 sq mi
Water area0.69 sq miThis ZIP0.69 sq mi

Other place names in 91901

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

ZIP codes near 91901

ZIPCityDistance
91903 Alpine, CA 2.7 mi
91931 Guatay, CA 8.7 mi
91916 Descanso, CA 8.7 mi
92021 El Cajon, CA 8.7 mi
91935 Jamul, CA 8.7 mi
92019 El Cajon, CA 8.7 mi
92040 Lakeside, CA 11.6 mi
91917 Dulzura, CA 12.0 mi
91962 Pine Valley, CA 12.2 mi
91963 Potrero, CA 13.7 mi

Find every ZIP code within 10 miles of 91901 →

Questions about this ZIP code

Where is ZIP code 91901?

91901 is in Alpine, California, in San Diego County, part of the San Diego-Chula Vista-Carlsbad, CA metropolitan area. Its published point location is 32.8136, -116.7270.

What county is 91901 in?

91901 lies in San Diego County.

What area code is 91901?

Alpine uses area codes 619 and 858, from NANPA's telephone records.

What time zone is 91901 in?

91901 uses America/Los_Angeles.

How many people live in 91901?

About 18,197 people live in ZIP code 91901, in 6,344 households, at 233.7 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 91901?

$114,167 a year, against $99,122 across California.

What ZIP codes are near 91901?

The closest are 91903 (2.7 mi), 91931 (8.7 mi), 91916 (8.7 mi), 92021 (8.7 mi) and 91935 (8.7 mi).

Is 91901 a PO Box ZIP code?

91901 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “91901 ZIP Code — Alpine, California (San Diego County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/91901

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