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zipcodes.pro — ZIP/54421

54421

ZIP 54421 is Colby, Wisconsin, mostly in Marathon County; area codes 715 and 534; Central time.

Type
Standard
Time zone
America/Chicago
County
Marathon +1 more
Metro area
Wausau, WI
Population
3,468
Coordinates
44.8952, -90.2887
☼ Live from 54421 — Colby, WI

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Local time: —

Where 54421 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 54421
  • 🔢 Type 54421 into a pocket calculator and turn it upside down: IZhhS — not quite a word, sorry.
  • ➕ 54421 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 16, a total 1,922 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1101010010010101
  • 🏠 Its numerical neighbours: 54420 (Chili, WI, 20 mi away) and 54422 (Curtiss, WI, 10 mi away).
  • 🔄 Backwards, 54421 becomes 12445, which is not a ZIP code at all.
  • 👥 35 other ZIP codes are made of exactly the same digits (12454, 12544, 14425, 14452, 14542, 15244, …). The farthest-flung twin is 12544 in Mellenville, NY, 850 miles away.
  • 🧭 Farther north than 91% of all ZIP codes, and farther west than 57%.
  • 🎯549 miles northeast of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 54421 and you would come out at 44.90°S, 89.71°E — 963 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 36m of daylight. Shortest: 8h 47m.
  • 📏 At 69.9 square miles of land, 54421 is bigger than 69% of ZIP codes — room for about 53 Central Parks.
🌙 The sky over 54421 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population3,468This ZIP3,468
Households1,170This ZIP1,170
Housing units1,215This ZIP1,215
Median age36.8This ZIP36.8Wisconsin40.2US 38.9
Median household income$60,820This ZIP$60,820Wisconsin$77,485US $80,734
Median home value$194,500This ZIP$194,500Wisconsin$266,500US $332,700
Median gross rent$844This ZIP$844Wisconsin$1,087US $1,413
Bachelor's degree or higher13.9%This ZIP13.9%
Mean commute18.7 minThis ZIP18.7 min
Population density49.6 / sq miThis ZIP49.6 / sq mi

Business and tax activity

Business establishments69This ZIP69
Employees951This ZIP951
Annual payroll$47,520,000This ZIP$47,520,000
Tax returns filed1,500This ZIP1,500
Total adjusted gross income$113,009,000This ZIP$113,009,000

Land area

Land area69.89 sq miThis ZIP69.89 sq mi
Water area0.12 sq miThis ZIP0.12 sq mi

Counties 54421 spans

A ZIP code is a mail route and ignores county lines. Shares are by overlapping land area.

CountyShare of this ZIP
Marathon County 55.1%
Clark County 44.9%

Other place names in 54421

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

ZIP codes near 54421

ZIPCityDistance
54488 Unity, WI 4.6 mi
54405 Abbotsford, WI 5.0 mi
54425 Dorchester, WI 8.1 mi
54422 Curtiss, WI 9.5 mi
54479 Spencer, WI 10.2 mi
54480 Stetsonville, WI 11.0 mi
54484 Stratford, WI 12.1 mi
54460 Owen, WI 12.6 mi
54446 Loyal, WI 13.4 mi
54426 Edgar, WI 14.3 mi

Find every ZIP code within 10 miles of 54421 →

Questions about this ZIP code

Where is ZIP code 54421?

54421 is in Colby, Wisconsin, in Marathon County, part of the Wausau, WI metropolitan area. Its published point location is 44.8952, -90.2887.

What county is 54421 in?

54421 spans 2 counties: Marathon County and Clark County. Most of it falls in Marathon County, measured by overlapping land area — the county holding the most land in a ZIP code is not always the one holding the most residents.

What area code is 54421?

Colby uses area codes 715 and 534, from NANPA's telephone records.

What time zone is 54421 in?

54421 uses America/Chicago.

How many people live in 54421?

About 3,468 people live in ZIP code 54421, in 1,170 households, at 49.6 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 54421?

$60,820 a year, against $77,485 across Wisconsin.

What ZIP codes are near 54421?

The closest are 54488 (4.6 mi), 54405 (5 mi), 54425 (8.1 mi), 54422 (9.5 mi) and 54479 (10.2 mi).

Is 54421 a PO Box ZIP code?

54421 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “54421 ZIP Code — Colby, Wisconsin (Marathon County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/54421

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/54421.json

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