Seattle to Sydney (Mascot)
15h 55m The flight from Seattle–Tacoma International Airport (SEA) to Sydney Kingsford Smith International Airport (SYD) covers 12,472 km (7,750 miles) and takes approximately 15h 55m gate to gate for a typical jet.
The route heads south-west on an initial great-circle bearing of 243°, passing near 9.2° N, 171.0° W at its midpoint.
The route
The great-circle path — the shortest line between the two airports across the curve of the earth. On a flat map it looks bent; on a globe it is straight.
Flight time at different cruise speeds
Aircraft type, winds and routing all move the real number. This is the same distance flown at different speeds, plus the 25-minute ground and climb allowance.
| Typical of | Cruise speed | Airborne | Gate to gate |
|---|---|---|---|
| Turboprop / regional | 550 km/h | 22h 41m | 23h 06m |
| Narrowbody jet (A320, 737) | 780 km/h | 15h 59m | 16h 25m |
| Widebody jet (777, 787, A350) | 900 km/h | 13h 51m | 14h 17m |
| Private jet (Gulfstream) | 850 km/h | 14h 40m | 15h 06m |
Headwinds on an eastbound long-haul routinely add 30–60 minutes; the same route westbound can be quicker. Airlines publish schedules with padding built in.
Both airports
| SEA | SYD | |
|---|---|---|
| Airport | Seattle–Tacoma International Airport | Sydney Kingsford Smith International Airport |
| City | Seattle | Sydney (Mascot) |
| Country | United States | Australia |
| ICAO | KSEA | YSSY |
| Coordinates | 47.4479, -122.3103 | -33.9461, 151.177 |
| Elevation | 433 ft | 21 ft |
Questions
How long is the flight from Seattle to Sydney (Mascot)?
A non-stop flight from Seattle (SEA) to Sydney (Mascot) (SYD) takes about 15h 55m. The great-circle distance is 12,472 km (7,750 miles, 6,734 nautical miles), flying south-west on an initial bearing of 243°.
How far is Seattle from Sydney (Mascot)?
12,472 kilometres in a straight line over the earth's surface — 7,750 miles or 6,734 nautical miles. Actual flown distance is usually 2–5% longer because aircraft follow airways, avoid weather and route around restricted airspace.
Is there a non-stop flight between SEA and SYD?
This page calculates the direct-line time and distance; it does not track airline schedules. At 12,472 km the route is within reach of long-range widebodies, though not every city pair is served non-stop. Check an airline or booking site for what is actually scheduled.
What should I expect on a 15h 55m flight?
Anything past six hours is a long-haul flight: expect at least one meal service, a significant time-zone shift, and enough sitting that circulation and hydration start to matter. Cabin altitude, dry air and disrupted sleep do more damage to a training routine than the flight itself.
Other routes from Seattle
Airport coordinates from OurAirports (public domain). Distance is a great-circle calculation; flight time uses the model described on the method page. Flight times are great-circle estimates for planning only — always check the airline's published schedule.