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Reference date and time
Related tools: Unix Time Converter Date Calculator Time Duration Calculator
Related article & poster: What Is Unix Time Unix Time Poster
Local time in each city
CityLocal date and timeOffset from UTC
Conversion relies on the IANA time zone database built into your browser. The dates on which daylight saving time starts and ends differ by country and region and can change from year to year, but the rules in force on the date you enter are applied automatically. Past and future dates are calculated with the offset that applied at that point in time.

Frequently asked questions (FAQ)

Is daylight saving time taken into account?

Yes. The conversion uses the IANA time zone database built into your browser, so it works out automatically whether daylight saving time is in effect on the date you enter. The same city can have a different offset in March than in December, and that difference is reflected correctly.

Is the date and time I enter sent to a server?

No. The conversion happens entirely in your browser using the JavaScript Intl API. Neither the date and time you enter nor the time zone you pick is ever sent to a server.

Can I treat UTC and GMT as the same thing?

In practice they are almost identical, but strictly speaking they are different concepts. UTC is coordinated universal time based on atomic clocks, while GMT derives from mean solar time at the Royal Observatory in Greenwich. The difference is under a second, so for everyday date and time conversion you can safely work from UTC.