Jet lag from San Francisco to Delhi: what to expect
Fly San Francisco to Delhi and local time runs 10½ hours behind your body. Land at 16:05 and your body still thinks it's 02:35 in San Francisco. That's the middle of your body's night. At 23:00 in Delhi, it's 09:30 for you.
That's a westward shift: your clock has to move later, which is the way it drifts on its own S1. Expect to be sleepy early in the evening for the first few days, and awake before your alarm S1.
At 10½ hours you're close to the far side of the world, where a clock could in principle shift either way. Adapting by delay is the more common route at that distance S1.
How long does jet lag last from San Francisco to Delhi?
Unaided, westward shifts settle somewhat faster than a day per time zone: about 7 days for this one. S6 S7
Your body can't go faster than ~7 days here. The plan's job is making them livable: protected sleep, no wrong-way light, functional days.
That's what the plan aims at, not a promise — bodies vary.
On night one, the evening after you land, the plan's bedtime is 19:40, early by Delhi's clock, and it moves later night by night, reaching 23:00 by night 7.
Studies of aircrew point the same way: after large shifts, westward adaptation runs roughly 50% faster than eastward S6 S8. This trip is on the quick side of that.
What does the plan say for a typical San Francisco to Delhi flight?
- Departs
- 11:00 San Francisco time
- Lands
- 16:05 Delhi time +1 day
- In the air
- about 15h 35m (estimate)
- Light, the first full day
- 17:25–18:25 Seek bright light (delay shift)
- Last caffeine, landing day
- 06:45 on the plane
- Caffeine after landing
- 22:40–11:45 landing night into the next day
- Nap after landing
- 17:35 Nap when you can lie down, up to 90 min
- First night's sleep
- 19:40–03:40 the evening after you land
Westbound flights often go by day, so this example leaves San Francisco at 11:00 and lands in Delhi at 16:05 in the afternoon, after about 15h 35m in the air.
The flight time is our estimate for a nonstop from the distance, and the trip is set in January. It's the default traveler from the calculator: usually asleep 23:00 to 07:00, no melatonin, Real Life effort.
You cross the date line, and it costs you a calendar day: leave on a Wednesday, land on Thursday, though the flight itself is under 16 hours.
In July the gap is 11½ hours, not 10½, because San Francisco moves its clocks for summer and Delhi doesn't.
The plan's sleep on board starts at 14:40 Delhi time and ends at 15:35, half an hour before you land: only 55 minutes. What's left of that night becomes a nap on the ground at 17:35: "Nap when you can lie down, up to 90 min".
You land at 16:05 and stay up through the local night, apart from the 17:35 nap: at 02:00 in Delhi your body thinks it's 12:30 in San Francisco, the middle of its day. It adds a 30-minute nap at 07:10. The first full night comes the next evening, at 19:40.
The day before you fly, the plan keeps your morning dim, 07:00–09:00 San Francisco time, and the sun is up in San Francisco by about 07:21 in January, so plan on sunglasses for the commute.
Your last coffee on the plane is at 06:45 Delhi time. After you land the plan opens caffeine again at 22:40, until 11:45 the next day: at 22:40 your body thinks it's 09:10 in San Francisco, its morning, and the plan keeps you up through the night on purpose.
The sun sets in Delhi at about 17:51 in January, partway through the 17:25 light step the day after landing, so start it outside.
You land too late in the day for a light step on landing day, so the first one is the next day, at 17:25.
What helps after flying west to Delhi?
Going west, you want light before your body's low point, which usually means bright light in the evening and staying up a little later S1. Bright light first thing in the morning works against you. East vs west explains why this direction is the easier one.
On a shift this size, starting before you fly pays off. The Frontiers review describes moving bedtime 30 to 60 minutes later each day for 3 to 4 days before a westward trip S1. The plan's version is one night: bed at 00:00 the night before you fly, an hour later than usual.
And the flight home from Delhi?
Delhi to San Francisco is the same 10½ hours the other way, eastward. It's the harder direction: about 11 days unaided, and the plan targets 9. Jet lag from Delhi to San Francisco has the details.
More routes from San Francisco
Sources
Numbered from the site-wide source registry — every Delagged page uses the same numbering.
- S1 Roach GD, Sargent C. Interventions to Minimize Jet Lag After Westward and Eastward Flight. Frontiers in Physiology, 2019;10:927. doi:10.3389/fphys.2019.00927
- S6 Waterhouse J, Reilly T, Atkinson G, Edwards B. Jet lag: trends and coping strategies. The Lancet, 2007;369:1117–29. doi:10.1016/S0140-6736(07)60529-7
- S7 Eastman CI, Burgess HJ. How to travel the world without jet lag. Sleep Medicine Clinics, 2009;4:241–55. doi:10.1016/j.jsmc.2009.02.006
- S8 Samel A, et al. Aircrew adaptation after transmeridian flights, 1995. As cited in Waterhouse et al., The Lancet 2007 (S6). Full text Cited via S6.