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World Clock

Live clocks for up to 12 IANA time zones, with offset and weekday.

Written by Golam Rabbani, Founder & Lead Engineer

Clocks update once per second using your browser's Intl tzdb. All zones are IANA identifiers.

Selected (4/12):

  • UTC
  • UTC
  • America/New_York
  • Europe/London

How to use this world clock

  1. Pick a time zone from the dropdown and press "+ Add" (up to 12 zones).
  2. Remove a zone by clicking the × next to its chip.
  3. Press "Show world clock" to start the live display.
  4. Read each zone’s current local time, weekday, and UTC offset.
  5. Use Copy to grab a tab-separated snapshot or Reset to start over.

About this world clock

A world clock lets you read the current time in several places at once. This one keeps everything in the browser using <code>Intl.DateTimeFormat</code> with IANA zone identifiers — no API calls, no network, and DST is handled automatically because your operating system already ships the zone data.

When you start the clock, the tool snapshots the current moment for every selected zone, formats it as <code>YYYY-MM-DD HH:MM:SS</code> with the localized weekday, and computes the offset from UTC. A one-second interval refreshes the snapshot so the table ticks in lockstep. You can add or remove zones at any time; the next tick re-renders the table with the new list.

Worked example: keep your local zone, add UTC, America/New_York, and Asia/Tokyo. At 10:00:00 on 28 May 2026 in London, the table shows London 10:00:00 (UTC+01:00), UTC 09:00:00, New York 05:00:00 (UTC-04:00), and Tokyo 18:00:00 (UTC+09:00) — all updating once a second. Press Copy and you get a tab-separated text block you can paste into a doc or chat.

Useful for remote teams, on-call rotations, family calls, trading desks, or anyone juggling multiple regions.

FAQ

How many zones can I track?
Up to 12. The cap keeps the table compact on phones and the render budget low for the per-second tick.
Are the offsets DST-correct?
Yes — each tick samples the current offset, so when a zone springs forward or falls back the displayed offset updates within a second.
Why am I not seeing a city I want?
The dropdown lists common zones. If you need one that is not listed, open an issue with the IANA identifier (for example, Asia/Kuala_Lumpur) and we will add it.
Does it work offline?
Yes after the first load. The page is a static component and there are no network calls.