How do I convert between time zones?

Select a source time zone, enter a date and time, then select up to 5 destination time zones. The converted times appear instantly. You can also add clocks to the world clock panel to see current times side by side.

Does this tool handle Daylight Saving Time?

Yes. This converter uses the browser's built-in Intl.DateTimeFormat API with full IANA time zone database support, which includes all DST transitions. The converted times automatically reflect whether DST is in effect on the chosen date.

What is UTC and how does it relate to time zones?

UTC (Coordinated Universal Time) is the primary time standard by which the world regulates clocks. All time zones are expressed as offsets from UTC. For example, US Eastern Standard Time is UTC-5 and Eastern Daylight Time is UTC-4.

Which cities are included in the world clock?

The world clock includes 30+ major cities: New York, Los Angeles, Chicago, Toronto, London, Paris, Berlin, Madrid, Rome, Amsterdam, Dubai, Mumbai, Singapore, Shanghai, Tokyo, Seoul, Sydney, Auckland, Sao Paulo, Buenos Aires, Mexico City, Cairo, Johannesburg, Istanbul, Moscow, and more.

What is the difference between EST and EDT?

EST (Eastern Standard Time) is UTC-5, used from November to March. EDT (Eastern Daylight Time) is UTC-4, used from March to November when Daylight Saving Time is in effect. The IANA identifier 'America/New_York' covers both automatically.

Time Zone Converter

Convert time between 30+ world time zones. DST-aware. See live current times side by side.

From Time Zone

→

Multiple targets below

Date & Time

Converted Times

Select a source time zone and enter a date/time to convert.

Live World Clock

Updates every second. Add up to 8 clocks.

How to Use the Time Zone Converter

Select your source time zone from the "From Time Zone" dropdown.
Enter a date and time using the datetime picker, or click "Set to Now" to use the current moment.
View converted times in the results panel — showing multiple major time zones at once.
Use the world clock below to see live current times in up to 8 cities simultaneously.
Copy results to paste a formatted time comparison into emails, Slack, or documents.

Understanding Time Zones

A time zone is a region of the globe that observes a uniform standard time for legal, commercial, and social purposes. There are 24 main time zones, each roughly 15 degrees of longitude wide, but in practice time zone boundaries follow political and geographical lines. The result is an irregular patchwork of over 600 IANA (Internet Assigned Numbers Authority) time zone identifiers that account for historical changes, DST rules, and sub-hour offsets.

Daylight Saving Time (DST)

Daylight Saving Time advances clocks by one hour during the warmer months to extend evening daylight. The US and Canada move clocks forward on the second Sunday in March and back on the first Sunday in November. The European Union (until potentially abolishing DST) moves on the last Sunday in March and October. Not all countries observe DST — China, Japan, India, and most countries near the equator do not. This tool uses the browser's Intl API with the IANA time zone database, which tracks all DST rules automatically.

UTC and GMT

UTC (Coordinated Universal Time) is the successor to GMT (Greenwich Mean Time) and the international standard for civil time. All time zones are defined as offsets from UTC — for example, UTC+5:30 is India Standard Time. For most practical purposes, UTC and GMT are interchangeable (they differ by at most 0.9 seconds, adjusted by leap seconds). When scheduling meetings across continents, always use UTC as the reference to avoid DST confusion.

Tips for International Scheduling

When scheduling meetings across time zones: always confirm whether the other party's country is currently in DST, since the UTC offset changes twice a year. Use IANA zone names (like "America/New_York") rather than abbreviations like "EST" — abbreviations are ambiguous (IST means India Standard Time, Irish Standard Time, and Israel Standard Time). Consider that some time zones have 30-minute or even 45-minute offsets from UTC (India UTC+5:30, Nepal UTC+5:45, Iran UTC+3:30). And remember that not all countries observe the same week boundaries — some Middle Eastern countries use a Sunday–Thursday work week.

Developer Notes

In JavaScript, time zone conversion uses the Intl.DateTimeFormat API with the timeZone option. This tool uses this same approach, which ensures DST-correct results. When storing datetimes in databases, always use UTC. When displaying to users, convert from UTC to their local time zone in the browser. Unix timestamps (seconds since 1970-01-01T00:00:00Z) are always UTC and are the safest format for API transmission. Avoid storing local time strings without a time zone offset attached.

Frequently Asked Questions

Select a source time zone, enter a date and time, and view the converted times in the results panel. You can also add clocks to the world clock section to see live current times side by side for up to 8 cities.

Yes. The converter uses the browser's Intl.DateTimeFormat API backed by the IANA time zone database, which includes all historical and future DST transitions. Converted times automatically reflect the correct UTC offset for the specific date chosen.

UTC (Coordinated Universal Time) is the primary world time standard. All time zones are UTC offsets — e.g., US Eastern Standard Time is UTC-5, Tokyo is UTC+9. UTC itself has no DST and is the preferred format for logging and API timestamps.

30+ major cities including New York, Los Angeles, London, Paris, Berlin, Dubai, Mumbai, Singapore, Tokyo, Seoul, Sydney, Auckland, São Paulo, Mexico City, Cairo, Johannesburg, Moscow, Istanbul, and more — covering all inhabited continents.

EST (Eastern Standard Time) is UTC-5, used November–March. EDT (Eastern Daylight Time) is UTC-4, used March–November during DST. The IANA identifier "America/New_York" covers both automatically and is what this tool uses internally.