JetSetAuthority

Route · Trans-Pacific

IAH Houston ⇄ SYD Sydney

George Bush Intercontinental Airport (United States) and Sydney Kingsford Smith International Airport (Australia): great-circle distance, estimated scheduled flight time each way, time difference and jet lag.

Distance13,836 km8,597 mi7,471 nautical miles
IAH → SYD17 h 25 minestimated block time
SYD → IAH16 h 10 minestimated block time
Clock change+16 hSydney vs Houston, today
Great-circle route from Houston (IAH) to Sydney (SYD)IAHHoustonSYDSydney
The shortest path over the Earth’s surface (great circle), drawn on a Natural Earth projection. Real flight paths bend around weather, winds and closed airspace.

Flight time each way

IAH → SYD

17 h 25 min

Estimated gate-to-gate scheduled time. Initial heading 247° (WSW).

Leave Houston Sat 7 Nov, 10:00 local → arrive Sydney Sun 8 Nov, 20:25 local +1 day.

SYD → IAH

16 h 10 min

Estimated gate-to-gate scheduled time. Initial heading 74° (ENE).

Leave Sydney Sat 7 Nov, 10:00 local → arrive Houston Sat 7 Nov, 09:10 local.

SYD-bound flights are the slower direction by about 75 minutes in our estimate: the route runs mostly east–west through latitudes where the prevailing westerly winds at cruise height are strong, so heading east rides a tailwind and heading west fights a headwind. How we estimate it.

Distance

Great-circle distance13,836 km · 8,597 mi · 7,471 nmi
Initial heading247° (WSW) from IAH; 74° (ENE) from SYD
Farthest from the equator33.9°S
Crossesthe equator and the 180th meridian (International Date Line area)
Share of the longest possible trip69% of the 20,015 km to the far side of the Earth

Time zones and jet lag

IAHAmerica/Chicago — UTC−5 now; UTC−6 standard time, UTC−5 during daylight saving time
SYDAustralia/Sydney — UTC+11 now; UTC+10 standard time, UTC+11 during daylight saving time
DifferenceSydney is 16 hours ahead of Houston today; +17 h in January and +15 h in July because daylight saving time starts and ends on different dates (or not at all).

Jet lag, flying IAH → SYD. The clock change is 16 hours, but to your body that is a shift of 8 hours the other way. Your body clock has to move 8 hours later, like a westward trip. A common rule of thumb is that the body clock adjusts by roughly one time zone a day, so expect up to about 8 days to fully adjust. Shifting later (as here) is usually the easier direction; evening daylight at the destination helps. Flying the other way, the shift is reversed.

General information, not medical advice.

The two airports

IAH George Bush Intercontinental AirportHouston, United States · longest runway 12,001 ft3,658 m SYD Sydney Kingsford Smith International AirportSydney, Australia · longest runway 12,999 ft3,962 m

More routes from IAH and SYD

DFWIAH Dallas–Fort Worth – Houston 362 km225 mi · 1 h 25 min IAHMEX Houston – Mexico City 1,232 km765 mi · 2 h 30 min IAHCUN Houston – Cancún 1,307 km812 mi · 2 h 30 min IAHBOG Houston – Bogotá 3,585 km2,228 mi · 5 h IAHLHR Houston – London 7,763 km4,824 mi · 9 h 15 min IAHFRA Houston – Frankfurt 8,402 km5,221 mi · 9 h 55 min SYDCBR Sydney – Canberra 236 km147 mi · 1 h 20 min SYDCHC Sydney – Christchurch 2,126 km1,321 mi · 3 h 15 min SYDMNL Sydney – Manila 6,263 km3,892 mi · 8 h 20 min HNLSYD Honolulu – Sydney 8,170 km5,077 mi · 10 h 35 min SFOSYD San Francisco – Sydney 11,950 km7,425 mi · 15 h 10 min LHRSYD London – Sydney 17,021 km10,576 mi · 19 h 30 min

Routes of a similar length

ATLJNB Atlanta – Johannesburg 13,583 km8,440 mi · 15 h 55 min SFOSIN San Francisco – Singapore 13,582 km8,439 mi · 17 h 45 min LAXSIN Los Angeles – Singapore 14,102 km8,762 mi · 18 h 25 min DXBAKL Dubai – Auckland 14,199 km8,823 mi · 16 h 30 min

Need a different pair? The flight-time calculator works for any two of 3,245 airports. Not covered: which airlines fly this route, schedules, fares and live status — that data is proprietary and we don’t guess it.

Photos on airport pages are credited there. Estimates are rounded to 5 minutes; typical error about 13 minutes (validation).