Hanoi is 16 hours ahead of Anchorage
Best overlap: 4:00 PM to 6:00 PM in Anchorage is 8:00 AM to 10:00 AM in Hanoi.
Schedule calls for 4:00 PM to 6:00 PM in Anchorage — your colleagues in Hanoi will be online from 8:00 AM to 10:00 AM. Hanoi is 16 hours ahead of Anchorage, so you only get about 2 hours of overlap a day — worth locking in a standing time like 4:00 PM in Anchorage (8:00 AM in Hanoi) before it slips. This window straddles two dates — Anchorage's today is Hanoi's the next day. These times hold for most of the year, but Anchorage's daylight saving (which Hanoi doesn't use) shifts them by an hour twice annually.