How to use the world clock
- The page opens with your own time zone plus New York, London and Tokyo. Each card shows the city, its zone abbreviation and UTC offset, the date, the live time, and how far ahead or behind you it is.
- Type a place in Add a city or time zone, such as Paris, Sydney or Mumbai, pick it from the suggestions or press Enter, then press Add clock. You can also type any IANA zone name, such as America/Phoenix or UTC.
- 24-hour clock switches the display between 12-hour and 24-hour. The x button removes a clock and Reset cities restores the starting set.
- Your list is kept in this browser only, up to 24 clocks.
How the times are worked out
The page asks your browser for the time in each zone using the standard Intl.DateTimeFormat API, which reads the IANA time zone database. For every zone it gets the UTC offset at this exact second, including daylight saving rules, so offsets change by themselves when clocks change. The ahead or behind figure is the difference between that zone's offset and yours right now. The DST badge appears when a zone's current offset is its larger yearly offset. US clocks follow the rule in the NIST daylight saving page: forward on the second Sunday of March (March 8, 2026) and back on the first Sunday of November (November 1, 2026). The UK changes on March 29 and October 25, 2026 (GOV.UK).
Worked example
Suppose your device is set to New York time and it is 12:00:00 PM on Thursday, January 1, 2026. Your card reads 12:00:00 PM with EST, UTC-5. The London card reads 5:00:00 PM, UTC+0, and says 5 h ahead of you. The Tokyo card reads 2:00:00 AM on Fri, Jan 2, UTC+9, and says 14 h ahead of you, tomorrow. In July New York is on EDT (UTC-4), so Tokyo is 13 hours ahead instead.
Limits and edge cases
- The times start from your device clock. If it is wrong, every card is wrong by the same amount.
- Governments sometimes change daylight saving rules at short notice. Your browser's time zone data comes with browser and system updates, so keep them current.
- About 100 popular cities are in the suggestions. Any other place works by its IANA name, for example Africa/Windhoek. Several cities share a zone, so Mumbai and Delhi both use Asia/Kolkata.
- Abbreviations like IST are ambiguous, so the UTC offset is shown beside them.
- To plan a meeting at one specific hour, use the time zone converter. To count down to a date, use countdown to date, and to be woken at a time, use the alarm clock.
Frequently asked questions
How do I see the current time in another country?
Type the city into Add a city or time zone and press Add clock. The card shows that city's local time, date and UTC offset, and it updates every second.
Why does the time difference between two cities change during the year?
Places start and end daylight saving time on different dates, or not at all. In 2026 the US moves clocks forward on March 8 but the UK waits until March 29, so from March 8 to 29 the gap between New York and London is 4 hours instead of 5.
What does the DST badge mean?
It means daylight saving time is in effect for that city right now, so its clocks are one hour ahead of standard time. Places that do not use daylight saving time, such as Arizona and Hawaii, never show it.
Does the world clock remember my cities?
Yes, in this browser only. If you clear site data or use a private window, the list returns to your own time zone plus New York, London and Tokyo.
Sources: IANA Time Zone Database; MDN, Intl.DateTimeFormat; NIST, Daylight Saving Time; GOV.UK, when do the clocks change. Checked October 2026.