If I want to fly around the world, should I travel west or east?

I keep getting confused about the effects of shorter days or longer days and can never figure out the dateline correctly.

  • 4
    Welcome to the site. Subjective questions asking 'what is best' often tend to get closed, as our help center indicates these don't belong. If you can edit your question to be more precise to indicate what you're after when you say 'best'? Shortest? Is this a single flight? Are you trying to reduce jetlag? Basically, what do you mean when you say 'best'.
    – Mark Mayo
    Commented Jul 9, 2013 at 8:20
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    A German professor had a conference in the USA and one in east-Asia. When he returned, he wanted reimbursed for 15 hotel nights. Unfortunately, he had been gone for only 14 nights; this problem could not be handled by German university bureaucracy.
    – gerrit
    Commented Jul 9, 2013 at 9:45

1 Answer 1


There are two effects I'm aware of:

  • Flying westwards will lengthen your subjective days (because you're moving against the rotation of the earth and thus staying longer in the same "day" relative to the sun). For most people, this reduces the effects of jet lag - you have a longer day, which is effectively like staying up late and sleeping in, just that it's still early morning when you wake up.
  • Flying eastwards will often lead to shorter flight times due to winds caused by the rotation of the earth.
  • Neither direction will magically give you more time :-) When you travel westwards, your days are longer, but you will lose an entire calendar day when you cross the international date line, exactly compensating the lengthened days. If you travel eastwards, you have shorter days but when you cross the date line, you get the same calendar day twice -

this is the plot twist at the end of "Around the World in Eighty Days").

If you have the choice, the reduced jet lag is probably more desirable.

  • Yes, that was what I was looking for. Commented Jul 9, 2013 at 10:10

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