To avoid confusion, time on schedules and public notices are typically formatted in the 24-hour system, so the times 19:45 and 07:45 are understood to be 12 hours apart from each other. Spoken Chinese predominantly uses the 12-hour system and follows the same concept as A.M. (N SH; shngw
) and P.M. (NSH; xiw
).

World Time Difference\n\n United States uses nine standard time zones from east to west. That means Beijing is 13 hours ahead of than Washington, New York, Boston, Atlanta; 14 hours ahead of Chicago; 16 hours ahead of San Francisco, Los Angeles, Seattle; 18 hours ahead of Hawaii, etc.