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zipcodes.pro — ZIP/21756

21756

ZIP 21756 is Keedysville, Maryland, in Washington County; area codes 240, 301 and 227; Eastern time.

Type
Standard
Time zone
America/New_York
County
Washington
Population
3,640
Coordinates
39.4598, -77.6935
☼ Live from 21756 — Keedysville, MD

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Where 21756 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 21756
  • 🔢 Type 21756 into a pocket calculator and turn it upside down: gSLIZ — not quite a word, sorry.
  • ➕ As a number, 21,756 = 2 × 2 × 3 × 7 × 7 × 37. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101010011111100
  • 🏠 Its numerical neighbours: 21755 (Jefferson, MD, 10 mi away) and 21757 (Keymar, MD, 25 mi away).
  • 🔄 Backwards, 21756 becomes 65712 — and that is a real ZIP code: Mount Vernon, MO, 888 miles away.
  • 👥 56 other ZIP codes are made of exactly the same digits (12567, 12765, 15267, 15276, 15627, 15672, …). The farthest-flung twin is 57621 in Bullhead, SD, 1,261 miles away.
  • 🧭 Farther north than 52% of all ZIP codes, and farther east than 79%.
  • 🎯1,109 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21756 and you would come out at 39.46°S, 102.31°E — 919 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 57m of daylight. Shortest: 9h 23m.
  • 📏 At 23.3 square miles of land, 21756 is bigger than 40% of ZIP codes — room for about 18 Central Parks.
🌙 The sky over 21756 today
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🌋 Shake report
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Source: USGS.

People and housing

Population3,640This ZIP3,640
Households1,394This ZIP1,394
Housing units1,496This ZIP1,496
Median age41.8This ZIP41.8Maryland39.4US 38.9
Median household income$101,786This ZIP$101,786Maryland$103,678US $80,734
Median home value$413,200This ZIP$413,200Maryland$419,900US $332,700
Median gross rent$1,321This ZIP$1,321Maryland$1,705US $1,413
Bachelor's degree or higher28.8%This ZIP28.8%
Mean commute44.4 minThis ZIP44.4 min
Population density156.3 / sq miThis ZIP156.3 / sq mi

Business and tax activity

Business establishments48This ZIP48
Employees161This ZIP161
Annual payroll$8,767,000This ZIP$8,767,000
Tax returns filed1,820This ZIP1,820
Total adjusted gross income$189,865,000This ZIP$189,865,000

Land area

Land area23.29 sq miThis ZIP23.29 sq mi
Water area0.01 sq miThis ZIP0.01 sq mi

Other place names in 21756

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

ZIP codes near 21756

ZIPCityDistance
21779 Rohrersville, MD 3.2 mi
21782 Sharpsburg, MD 3.6 mi
21713 Boonsboro, MD 4.7 mi
21718 Burkittsville, MD 5.8 mi
21715 Brownsville, MD 5.9 mi
25443 Shepherdstown, WV 6.6 mi
21769 Middletown, MD 6.8 mi
21733 Fairplay, MD 7.1 mi
21746 Hagerstown, MD 7.4 mi
21758 Knoxville, MD 7.6 mi

Find every ZIP code within 10 miles of 21756 →

Questions about this ZIP code

Where is ZIP code 21756?

21756 is in Keedysville, Maryland, in Washington County, part of the Hagerstown-Martinsburg, MD-WV metropolitan area. Its published point location is 39.4598, -77.6935.

What county is 21756 in?

21756 lies in Washington County.

What area code is 21756?

Keedysville uses area codes 240, 301 and 227, from NANPA's telephone records.

What time zone is 21756 in?

21756 uses America/New_York.

How many people live in 21756?

About 3,640 people live in ZIP code 21756, in 1,394 households, at 156.3 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 21756?

$101,786 a year, against $103,678 across Maryland.

What ZIP codes are near 21756?

The closest are 21779 (3.2 mi), 21782 (3.6 mi), 21713 (4.7 mi), 21718 (5.8 mi) and 21715 (5.9 mi).

Is 21756 a PO Box ZIP code?

21756 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21756 ZIP Code — Keedysville, Maryland (Washington County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21756

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