How Many Time Zones Are There in the World?

There is no single official count. Twenty-four is the textbook answer, one band for each hour. Counting the zones on this site's list, 37 different UTC offsets were in use on 31 October 2026 and 39 during the year. The raw time zone database adds a UTC-12 name, so its count is one higher.

By World Date and Time editorial team · Published 31 October 2026

“How many time zones are there?” can mean three different things. The first is the hourly bands of the textbook map, which gives 24. The second is the number of distinct offsets from UTC that clocks actually use. On 31 October 2026, clocks showed 37 different offsets from UTC. Across the whole of 2026 the count is 39, because daylight saving brings some offsets in for part of the year and takes others out. The third is the number of names in the IANA Time Zone Database, the list that phones and servers read. Its file zone1970.tab has 312 rows. The sources cited here do not give one official count, so this guide gives each number with the rule behind it.

Why 24 is not the whole story

The Earth turns through 360° in a day, which is 15° an hour, so 24 bands of one hour is the starting picture. The tz database notes say the link between longitude and the clock is loose: “Although a zone1970.tab location’s longitude corresponds to its local mean time (LMT) offset with one hour for every 15° east longitude, this relationship is not exact” (Theory and pragmatics). Civil clocks follow governments, not meridians. The IANA page says the database “is updated periodically to reflect changes made by political bodies to time zone boundaries, UTC offsets, and daylight-saving rules”.

Every UTC offset in use in 2026

The table reads each of this site's 422 zone names once an hour through 2026, using tzdata 2026f, and lists every distinct offset it finds. There are 39: 26 whole-hour offsets from UTC-11 to UTC+14, and 13 that are not whole hours. “Zone names” counts names, not places, because some names are aliases of the same place.

Method: Each of the site's 422 zone names read once an hour from 1 January to 31 December 2026 (UTC) with tzdata 2026f. "Zone names" counts names, and some names are aliases of one place, so it does not count places. A day counts as in use if any zone name had that offset for any part of it.

The offsets that are not whole hours

13 of the 39 offsets in use during 2026 are not whole hours: UTC-9:30, UTC-3:30, UTC-2:30, UTC+3:30, UTC+4:30, UTC+5:30, UTC+5:45, UTC+6:30, UTC+8:45, UTC+9:30, UTC+10:30, UTC+12:45 and UTC+13:45. They are not rare curiosities. Asia/Kolkata (UTC+5:30) is the clock for India, and Asia/Colombo uses it too. Asia/Tehran and Asia/Kabul sit on UTC+3:30 and UTC+4:30. Nepal is on UTC+5:45 (Asia/Katmandu). The database spells the name Asia/Kathmandu and records UTC+5:30 until 1986 and UTC+5:45 after (asia).

Australia/Eucla is at UTC+8:45. The notes in the database quote a 2006 account that along the Eyre Highway “UTC+08:45 was considered “the time”” from the border village to just east of Caiguna (australasia). Pacific/Chatham keeps UTC+12:45 in winter and UTC+13:45 in summer. The same file says: “Since 1957 Chatham has been 45 minutes ahead of NZ”. America/St_Johns is UTC-3:30 in winter and UTC-2:30 in summer.

The two ends: UTC-11 and UTC+14

On the site's list, the lowest offset in use in 2026 is UTC-11 and the highest is UTC+14, 25 hours apart. The highest belongs to Pacific/Kiritimati. That span has a side effect: any calendar date is on some clock somewhere for 49 hours, from the moment it begins in UTC+14 to the moment it ends in UTC-11. That figure follows from the two offsets. It is not quoted from a source.

The ends have moved. In the database, Pacific/Kiritimati is UTC-10:00 from October 1979 until 1994 Dec 31 and UTC+14:00 after. Pacific/Apia is UTC-11:00 (with daylight saving) until 2011 Dec 29 24:00 and UTC+13:00 after. Pacific/Kwajalein is UTC-12:00 from October 1969 until 1993 Aug 20 24:00 and UTC+12:00 after (australasia). The database still has a UTC-12 name, Etc/GMT+12, with the sign written the POSIX way (etcetera). No name on this site's list uses UTC-12 in 2026, so the counts here do not include it. A count taken straight from the raw database, with Etc/GMT+12 included, would be 38 on 31 October and 40 across the year.

How daylight saving changes the count

Counting on one day gives 37 on 15 January, 15 July, 31 October and 2 November alike, but not the same 37. The table shows which two offsets each day is missing. On 1 November 2026, when US clocks fall back, America/St_Johns returns to UTC-3:30 and UTC-2:30 drops out, so the total holds at 37 while the set changes.

Method: Each of the site's 422 zone names read at 12:00 UTC on the day. Time zone data: tzdata 2026f.

131 of the 422 zone names change offset at least once in 2026. Nearly all move by one hour. The two exceptions are Australia/Lord_Howe, which moves 30 minutes (the notes say Lord Howe Island “advances clocks by 30 minutes during DST”; australasia), and Antarctica/Troll, which moves two hours (the file’s notes say the station’s own rules are more involved and it approximates “with only UTC and CEST”; antarctica). The daylight saving pages list the change dates by country, and the daylight saving guide covers the basics.

What the 312 rows mean

A row in zone1970.tab is a location used to name a zone. One of the database's naming goals is to “Uniquely identify every timezone where clocks have agreed since 1970” (Theory and pragmatics). Two places can share an offset today and still have separate rows because their clocks differed after 1970. That is why 312 is so much larger than 39: UTC+2 alone is used by 68 zone names on this site's list in 2026. The row count is from the file on 31 October 2026 (release 2026f). A country that spans many degrees of longitude can still run one clock, as in why China has one time zone.

Which number to use

For software, store the zone name, such as Europe/London, not an offset or an abbreviation. An offset forgets daylight saving, and an abbreviation can name two zones. To compare places, use the time zone converter or the meeting planner. The tools below show the zone list, the map and the live clocks.

Method and version. The counts use tzdata 2026f, the time zone data the build loads from the repository, and are saved in the repository so every reader sees the same numbers. IANA released 2026f on 27 October 2026. Its notice reads “Cuba will not fall back 2026-11-01; stays on -04 through 2027-11-07” (IANA). Havana therefore stays on UTC-4 after 1 November 2026, through 7 November 2027, instead of falling back to UTC-5. Both offsets are in use elsewhere, and these counts already use 2026f, so the change does not alter the list above.