The time in Thailand is Greenwich Mean Time (GMT) +7 hours

Because Thailand does not operate Daylight-Saving Time, giving a fixed calculation for other world cities is not useful.  Also since Thailand is west of the International Date Line it is always confusing to what day it is.  Click on the link below to see the current Bangkok time and compare it to times (and dates) for other world cities. 

Note: Very often the time in Thailand will be given in 24 hour time, aka Military Time.

World times from TimeAndDate.com