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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/01581

01581

ZIP 01581 is Westborough, Massachusetts, in Worcester County; area codes 508 and 774; Eastern time.

Type
Standard
Time zone
America/New_York
County
Worcester
Metro area
Worcester, MA
Population
21,944
Coordinates
42.2684, -71.6133
☼ Live from 01581 — Westborough, MA

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Where 01581 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 01581
  • 🔢 Type 01581 into a pocket calculator and turn it upside down: IBSIO — not quite a word, sorry.
  • ➕ As a number, 1,581 = 3 × 17 × 31. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 11000101101
  • 🏠 Its numerical neighbours: 01571 (Dudley, MA, 22 mi away) and 01583 (West Boylston, MA, 12 mi away).
  • 🔄 Backwards, 01581 becomes 18510 — and that is a real ZIP code: Scranton, PA, 216 miles away.
  • 👥 25 other ZIP codes are made of exactly the same digits (01518, 01815, 01851, 08511, 10158, 10185, …). The farthest-flung twin is 85011 in Phoenix, AZ, 2,267 miles away.
  • 🧭 Farther north than 77% of all ZIP codes, and farther east than 95%.
  • 🎯1,409 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 01581 and you would come out at 42.27°S, 108.39°E — 822 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 16m of daylight. Shortest: 9h 05m.
  • 📏 At 20.6 square miles of land, 01581 is bigger than 38% of ZIP codes — room for about 16 Central Parks.
🌙 The sky over 01581 today
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🌋 Shake report
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Source: USGS.

People and housing

Population21,944This ZIP21,944
Households7,964This ZIP7,964
Housing units8,342This ZIP8,342
Median age38.8This ZIP38.8Massachusetts40.0US 38.9
Median household income$141,944This ZIP$141,944Massachusetts$103,960US $80,734
Median home value$685,300This ZIP$685,300Massachusetts$562,100US $332,700
Median gross rent$2,106This ZIP$2,106Massachusetts$1,762US $1,413
Bachelor's degree or higher65.2%This ZIP65.2%
Mean commute28.5 minThis ZIP28.5 min
Population density1,064.9 / sq miThis ZIP1,064.9 / sq mi

Business and tax activity

Business establishments955This ZIP955
Employees30,063This ZIP30,063
Annual payroll$2,445,537,000This ZIP$2,445,537,000
Tax returns filed10,180This ZIP10,180
Total adjusted gross income$1,554,523,000This ZIP$1,554,523,000

Land area

Land area20.61 sq miThis ZIP20.61 sq mi
Water area0.86 sq miThis ZIP0.86 sq mi

Other place names in 01581

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

ZIP codes near 01581

ZIPCityDistance
01784 Woodville, MA 3.4 mi
01532 Northborough, MA 4.2 mi
01536 North Grafton, MA 4.8 mi
01748 Hopkinton, MA 4.8 mi
01772 Southborough, MA 4.8 mi
01545 Shrewsbury, MA 5.3 mi
01519 Grafton, MA 5.6 mi
01745 Fayville, MA 6.1 mi
01568 Upton, MA 6.3 mi
01752 Marlborough, MA 6.5 mi

Find every ZIP code within 10 miles of 01581 →

Questions about this ZIP code

Where is ZIP code 01581?

01581 is in Westborough, Massachusetts, in Worcester County, part of the Worcester, MA metropolitan area. Its published point location is 42.2684, -71.6133.

What county is 01581 in?

01581 lies in Worcester County.

What area code is 01581?

Westborough uses area codes 508 and 774, from NANPA's telephone records.

What time zone is 01581 in?

01581 uses America/New_York.

How many people live in 01581?

About 21,944 people live in ZIP code 01581, in 7,964 households, at 1,064.9 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 01581?

$141,944 a year, against $103,960 across Massachusetts.

What ZIP codes are near 01581?

The closest are 01784 (3.4 mi), 01532 (4.2 mi), 01536 (4.8 mi), 01748 (4.8 mi) and 01772 (4.8 mi).

Is 01581 a PO Box ZIP code?

01581 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “01581 ZIP Code — Westborough, Massachusetts (Worcester County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/01581

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