# 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
Coordinates: 38°56′40″N, 77°27′20″W

B Decatur Airport
City: Decatur, IL
Country: 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..

EST

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?