Skip to main content
TimeZonar

DST change tracker

Every clock change worldwide in the next 12 months, your places' next change, and when two places' gap shifts.

How the tracker finds changes

There's no list of change dates to look up: each country sets its own rules, and they're recorded in the IANA time zone database that your browser carries.[1] When you open this page, it checks every time zone your browser knows for the next 12 months and notes each moment an offset changes, to the minute. Changes on the same day in the same direction are grouped into one entry.

Because the dates come from your browser, they're only as current as its data. Browsers and phones get updates when a government changes its rules, so keep yours up to date. A country that changed its rules recently may show the old dates on an out-of-date device.

Why the dates differ by country

  • United States: the second Sunday in March and the first Sunday in November, at 2:00 AM local time, so each US zone changes at a different moment.[2]
  • European Union: the last Sundays in March and October, at 01:00 UTC, so every EU country changes at the same instant whatever its local time.[3]
  • United Kingdom: the same Sundays as the EU, at 1:00 AM in spring and 2:00 AM in autumn.[4]

That's why the worldwide list has two big autumn dates a week apart, one for Europe and one for North America, and why the gap between them shifts for those weeks. The rules for each region are in the daylight saving time guide.

Northern vs southern hemisphere

Summer comes at opposite times of year in the two hemispheres, so their clocks move in opposite directions. When Europe and North America go back in October and November, southeastern Australia and New Zealand have recently gone forward:

  • Australia (New South Wales, Victoria, South Australia, Tasmania and the ACT): forward on the first Sunday in October, back on the first Sunday in April.[5]
  • New Zealand: forward on the last Sunday in September, back on the first Sunday in April.[6]

So the gap between London and Sydney swings by two hours across the year. Use "Two places" above to see exactly when.

What happens on change night

When clocks go forward, an hour is skipped: in the US, 1:59 AM is followed by 3:00 AM.[2] When they go back, an hour repeats. Calendar software handles this by reading a skipped time with the offset from before the jump, and a repeated time as its first occurrence.[7]

Each entry in the worldwide list shows the local time on the clocks just before the change, so you can see which hour disappears or repeats in each place.

Countries that stopped changing their clocks

  • Mexico ended daylight saving time in 2022, except in towns along the US border, which still follow the US dates.[8]
  • Brazil abolished it in 2019, after decades of changing its clocks.[9]

When a country stops, its entries simply disappear from the tracker once your browser has the updated data. Most of Asia and Africa don't change their clocks at all.

Planning around changes

  • Recurring meetings stay at the same local time for the organizer, so they move by an hour for anyone whose clocks change on a different date.[7] Check the weeks between the US and European change dates. More in scheduling across time zones.
  • Travel: if a trip crosses a change date, every time on your schedule after it moves by an hour. Follow your destination under "Your places".
  • Alarms and devices: phones and computers change on their own; ovens, car clocks and older wall clocks usually don't.
  • Servers and scheduled jobs: a job set for a local time inside the skipped or repeated hour may not run, or may run twice. Scheduling in UTC avoids both.

DST proposals and debate

Checked October 4, 2026.

  • European Union: the European Parliament voted in 2019 to end the twice-yearly changes, but member states couldn't agree whether to keep summer or winter time, and the plan has stalled.[10]
  • United States: the House of Representatives passed the Sunshine Protection Act in July 2026, which would keep the country on daylight saving time all year. It still needs to pass the Senate and be signed into law.[11]

If either becomes law, the tracker will show it as soon as your browser's time zone data includes the new rules.

Developer notes

To find a zone's next change in JavaScript, Temporal has a method made for it:[12]

Temporal.Now.zonedDateTimeISO("Europe/London")
  .getTimeZoneTransition("next");
// the first instant on the new offset, or null if there's none

Temporal isn't in every browser yet.[13] Without it, do what this page does: sample the zone's offset with Intl.DateTimeFormat across the period, and narrow down to the minute wherever it changes. In Python, read offsets with zoneinfo the same way, and add the tzdata package where the system has no time zone data.[14]

  • Test around changes: the skipped and repeated hours, a half-hour change (Lord Howe Island), and a zone that suspends summer time for part of the year (Morocco, around Ramadan).
  • Keep the data current: rules change somewhere most years, and old data gives wrong dates.[1]
  • Calendar files: the export above writes an RFC 5545 .ics file with an event at each change, in UTC.[7]

More in programming with time zones.

Frequently asked questions

When do the clocks change next?

The line at the top of "Worldwide" says, with a countdown. For your own place, open "Your places": your time is always listed first.

Do the clocks go forward or back?

Forward in spring and back in autumn, which is March to April and September to November depending on the hemisphere. Each entry shows the direction with an arrow.

Why does a place I know not appear?

It doesn't change its clocks in the next 12 months. Add it under "Your places" to confirm.

Can I get reminders?

Add your places, then use "Add these changes to my calendar". Your calendar app will remind you like any other event.

Sources

  1. 1.IANA, Time Zone Database. The record of every place's clock-change rules that browsers ship, updated when governments change them.
  2. 2.U.S. Department of Transportation, Daylight Saving Time. US change dates, at 2:00 a.m. local time.
  3. 3.EUR-Lex, Directive 2000/84/EC on summer-time arrangements. EU change dates, all at 01:00 UTC.
  4. 4.GOV.UK, When do the clocks change?. UK change dates and times.
  5. 5.NSW Communities and Justice, Daylight saving. Australian change dates and the states that take part.
  6. 6.New Zealand Government, Daylight saving. New Zealand change dates.
  7. 7.IETF, RFC 5545: Internet Calendaring and Scheduling (iCalendar). How calendars read skipped and repeated times, and the calendar file format the export uses.
  8. 8.Bloomberg Línea, Mexico abolishes daylight saving time. Mexico ending daylight saving in 2022, except near the US border.
  9. 9.Associated Press, via Anchorage Daily News, Brazil eliminated daylight saving time. It's having second thoughts. Brazil abolishing daylight saving time in 2019.
  10. 10.The Local, Whatever happened to the EU plan to ditch the changing of the clocks?. The European Parliament's 2019 vote and why the plan stalled.
  11. 11.NBC News, House passes bill that would make daylight saving time permanent. The House vote on the Sunshine Protection Act in July 2026.
  12. 12.MDN, Temporal.ZonedDateTime.prototype.getTimeZoneTransition(). Finding the next or previous offset change of a zone.
  13. 13.MDN, Temporal. Temporal's limited browser availability.
  14. 14.Python documentation, zoneinfo: IANA time zone support. Reading offsets from IANA zones in Python, and the tzdata package.

Related pages