How far is Washington D.C. from Portsmouth, NH?
The distance between Portsmouth (Portsmouth International Airport at Pease) and Washington D.C. (Washington Dulles International Airport) is 449 miles / 722 kilometers / 390 nautical miles.
The driving distance from Portsmouth (PSM) to Washington D.C. (IAD) is 510 miles / 820 kilometers, and travel time by car is about 10 hours 33 minutes.
Portsmouth International Airport at Pease – Washington Dulles International Airport
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Distance from Portsmouth to Washington D.C.
There are several ways to calculate the distance from Portsmouth to Washington D.C.. Here are two standard methods:
Vincenty's formula (applied above)- 448.683 miles
- 722.085 kilometers
- 389.895 nautical miles
Vincenty's formula calculates the distance between latitude/longitude points on the earth's surface using an ellipsoidal model of the planet.
Haversine formula- 448.230 miles
- 721.356 kilometers
- 389.501 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).
How long does it take to fly from Portsmouth to Washington D.C.?
The estimated flight time from Portsmouth International Airport at Pease to Washington Dulles International Airport is 1 hour and 20 minutes.
What is the time difference between Portsmouth and Washington D.C.?
There is no time difference between Portsmouth and Washington D.C..
Flight carbon footprint between Portsmouth International Airport at Pease (PSM) and Washington Dulles International Airport (IAD)
On average, flying from Portsmouth to Washington D.C. generates about 91 kg of CO2 per passenger, and 91 kilograms equals 201 pounds (lbs). The figures are estimates and include only the CO2 generated by burning jet fuel.
Map of flight path and driving directions from Portsmouth to Washington D.C.
See the map of the shortest flight path between Portsmouth International Airport at Pease (PSM) and Washington Dulles International Airport (IAD).
Airport information
| Origin | Portsmouth International Airport at Pease |
|---|---|
| City: | Portsmouth, NH |
| Country: | United States  |
| IATA Code: | PSM |
| ICAO Code: | KPSM |
| Coordinates: | 43°4′40″N, 70°49′23″W |
| Destination | Washington Dulles International Airport |
|---|---|
| City: | Washington D.C. |
| Country: | United States |
| IATA Code: | IAD |
| ICAO Code: | KIAD |
| Coordinates: | 38°56′40″N, 77°27′20″W |