Sleep Calculator by City

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Shift your schedule toward the new time zone for a few days before you leave if you can, choose flight sleep to match night at the destination, get daylight at the right time after landing and keep the first nights steady. Many travelers adjust about one hour of time difference per day.

CDC guidance lists 8 to 10 hours for ages 13 to 18, 9 to 12 hours for ages 6 to 12, 10 to 13 hours for ages 3 to 5 including naps, and 11 to 14 hours for ages 1 to 2 including naps.

Yes. A regular sleep and wake time supports your body clock, which can make it easier to fall asleep and wake up. Large gaps between weekday and weekend times can leave you feeling jet lagged on Monday.

Most adults do well with 5 cycles (about 7.5 hours) and some need 6 (about 9 hours). Four cycles, about 6 hours, is short for most people and is better used as an occasional fallback than a habit.

Eastward travel is usually harder because you must fall asleep earlier than your body clock wants. Westward travel asks you to stay up later, which is generally easier.

For most adults it is below the recommended 7 hours. Some people feel fine for a while, but research on chronic sleep restriction found that performance slips even when people do not feel very sleepy. Treat 6 hours as a short night and plan recovery sleep.