No letter or w: wall clock time, actual local time. Important: sometimes the time is followed by a letter. 'Sat' is a Saturday, 'Fri' is a Friday, 'Thu' is a Thursday, etcetera.Īpr Sun>=1: means the first Sunday on or immediately after April 1. Mar lastSun: means the last Sunday of March. Date: Date formula for the DST switch.'off' means: from this date on the standard time (winter time) is observed. on/off: 'on' means: from this date on daylight saving is observed, sometimes called 'summer time'.The last transition stays in effect until the next transition or if there is none, then indefinitely. The Rule lines in the TZ database itself mark transitions in time. Valid: Sometimes a rule is only valid within a certain period of time.DST rule name: An arbitrary abbreviation for the daylight saving rule.Divide the number of degrees in longitude by 15. The LMT time is calculated from the geographic longitude of a local place. Over a year the equation of time can make a difference of between about + and - 18 minutes with the mean LMT time. This means that the sun is at its highest point at local time:ġ2 + zonetime + DST - LMT - EquationOfTimeĮxample: Kaxgar, China location: 39:29°N, 075:59☎ LMT: 5:03:56 zone: 8 DST: 0 EoT on : -0:06:28 this gives local time 15:02:32. Right then the sun passes the local meridian and is at its highest point in the sky. At the moments where the equation of time is zero, this is the amount of time to be added to UTC. This is the 'natural' mean solar time for a location, excluding the equation of time. 'DST rule' is the name of the rules, describing the on/off date and time for the daylight saving. DST rule: Some countries use daylight saving time (DST).Where two abbreviations are given, the first one is for standard time, the second for daylight saving time. In most cases this is not an official abbreviation. Time: An abbreviation of the time designation.Zone time: the amount of hours:minutes to be added to the time at the zero meridian of Greenwich (UTC) to get the local time.A list with alternative descriptions (not TZ endorsed!) could give a clue. Just looking at a TZ zone name, it is in many cases not immediately clear to what geographical region the name refers. The name is usually derived from a central place or the place with the most inhabitants, not necessarily the capital. TZ zone name: the Unix TZ string time zone name as listed in the 'tz database'.Sometimes there seems to be no difference with other zones for the same country. District(s): Some countries have more than one time zone.Complete timezone information for all countriesĪ listing of all known time zone information for current use.Ī description of the table columns will clarify this.

Country time zones