Schedule a meeting across time zones without a date mistake

How to calculate it

A time-zone offset is the difference from UTC for a particular instant, not a permanent property of a city. Pick the meeting date first, note the source and destination locations, then convert the time and check whether the calendar day changes. Some regions observe daylight saving and change offsets during the year, while others do not. A fixed offset calculator is useful for a known date, but must be updated when either location changes its rule or season.

Worked example

If one city is UTC+3 and another is UTC−4 on the meeting date, the difference is seven hours. A call at 18:00 in the first city is 11:00 in the second on the same day. At 02:00, it is 19:00 on the previous day. If the second city later changes to UTC−5, the difference becomes eight hours; do not reuse the earlier conversion for a winter meeting. Spell out the date beside each local time.

What can change the result

An abbreviation such as CST can mean different regions. Avoid it in invitations; write the named city or IANA time zone and include a calendar invitation that resolves the actual date. Ambiguous or missing local times can occur when clocks change. Verify the converted time with a current calendar service before sending, especially around transition weekends.

Use the calculators and keep reading

Use the time-zone offset calculator to check the arithmetic and the date calculator if the appointment crosses midnight. Include both local dates and UTC in the invitation. The linked calendar-date guide explains why moving by one month is not the same as moving by a fixed number of days.

Try the time zone offset, date add calculator and read this related article for the context and assumptions.