Air Miles Calculator

Distance between Washington D.C. (IAD) and Decatur, IL (DEC)

Flight distance from Washington D.C. to Decatur (Washington Dulles International Airport – Decatur Airport) is 613 miles / 987 kilometers / 533 nautical miles. Estimated flight time is 1 hour 39 minutes.

Driving distance from Washington D.C. (IAD) to Decatur (DEC) is 733 miles / 1179 kilometers and travel time by car is about 13 hours 15 minutes.

Map of flight path and driving directions from Washington D.C. to Decatur.

Shortest flight path between Washington Dulles International Airport (IAD) and Decatur Airport (DEC).

How far is Decatur from Washington D.C.?

There are several ways to calculate distances between Washington D.C. and Decatur. Here are two common methods:

Vincenty's formula (applied above)
  • 613.435 miles
  • 987.229 kilometers
  • 533.061 nautical miles

Vincenty's formula calculates the distance between latitude/longitude points on the earth’s surface, using an ellipsoidal model of the earth.

Haversine formula
  • 611.948 miles
  • 984.835 kilometers
  • 531.768 nautical miles

The haversine formula calculates the distance between latitude/longitude points assuming a spherical earth (great-circle distance – the shortest distance between two points).

Airport information


A Washington Dulles International Airport
City: Washington D.C.
Country: United States Flag of United States
IATA Code: IAD
ICAO Code: KIAD
Coordinates: 38°56′40″N, 77°27′20″W

B Decatur Airport
City: Decatur, IL
Country: United States Flag of United States
IATA Code: DEC
ICAO Code: KDEC
Coordinates: 39°50′4″N, 88°51′56″W

Time difference and current local times

The time difference between Washington D.C. and Decatur is 1 hour. Decatur is 1 hour behind Washington D.C..

Time Difference

Washington D.C.

 EST

Decatur, IL

 CST

Carbon dioxide emissions

Estimated CO2 emissions per passenger is 114 kg (252 pounds).

Frequent Flyer Miles Calculator

Washington D.C. (IAD) → Decatur (DEC).

Distance:
613
Elite level bonus:
0
Booking class bonus:
0

In total

Total frequent flyer miles:
613

Round trip?