Reference tools for planning across places and times
Reference tools answer questions where the rules come from the real world rather than a formula — time zones, daylight saving changes and calendars.
The time zone converter compares one moment across many cities at once. It shows each city’s UTC offset, flags when a time falls on the previous or next day, and colours the hours that fall inside a normal working day, which makes it easy to find a meeting slot that suits everyone.
How time zone data works
Time zone rules change more often than most people expect. Countries adjust daylight saving dates or move to a new offset, sometimes with only a few months’ notice. This converter uses the time zone database built into your browser, the same data your operating system relies on, so it stays current as your browser updates. No time zone data is downloaded from our servers.
Related tools
For converting between timestamps and dates, use the Unix timestamp converter. To count days between two dates or add a period to a date, use the date difference calculator.