Scheduling Across Five Time Zones: A UTC-Offset Meeting Planner
October 21, 2026
Planning a call across continents is a puzzle of offsets. The safest approach is to convert everything through UTC (Coordinated Universal Time), the reference with no daylight saving. Each time zone is defined by its offset from UTC, such as UTC−5 for New York in winter or UTC+9 for Tokyo. To convert a time from zone A to zone B: subtract A's offset to get UTC, then add B's offset.
For example, on November 10, 2026, New York is on standard time (UTC−5), London is on GMT (UTC+0), Mumbai is UTC+5:30, Tokyo is UTC+9, and Sydney is on daylight time (UTC+11). A 9:00 a.m. meeting in New York is 14:00 UTC, which is 2:00 p.m. in London, 7:30 p.m. in Mumbai, 11:00 p.m. in Tokyo, and 1:00 a.m. the next day in Sydney.
Skip the math and get your answer instantly:
Open the Time Calculator →Offsets for Major Cities
Offsets change when regions switch to or from daylight saving time. The table shows common offsets in the northern winter and summer. Many places, including India, Japan, and China, do not observe DST, while Australia's DST runs in the southern summer, roughly October to April.
Note that some zones have non-whole-hour offsets, such as India (UTC+5:30), Nepal (UTC+5:45), and parts of Australia (UTC+9:30 for Adelaide).
| City | Winter (northern) | Summer (northern) |
|---|---|---|
| New York | UTC−5 | UTC−4 |
| London | UTC+0 | UTC+1 |
| Mumbai | UTC+5:30 | UTC+5:30 |
| Tokyo | UTC+9 | UTC+9 |
| Sydney | UTC+11 | UTC+10 |
| Los Angeles | UTC−8 | UTC−7 |
Worked Conversion
Convert 9:00 a.m. in New York (UTC−5) to Mumbai (UTC+5:30). UTC time = 9:00 + 5:00 = 14:00. Mumbai time = 14:00 + 5:30 = 19:30. Going the other way, 10:00 a.m. in Mumbai is 10:00 − 5:30 = 4:30 UTC, which is 11:30 p.m. the previous evening in New York (4:30 − 5:00 = −0:30).
When the result crosses midnight, adjust the date: a negative time means the previous day, and a time of 24:00 or more means the next day.
Finding Overlapping Working Hours
Convert each team's working window to UTC, then find the intersection. If New York works 9:00 to 17:00 (14:00 to 22:00 UTC in winter) and London works 9:00 to 17:00 (9:00 to 17:00 UTC), the overlap is 14:00 to 17:00 UTC, or 9:00 a.m. to noon in New York, and 2:00 to 5:00 p.m. in London. Add Mumbai (3:30 to 11:30 UTC for a 9:00 to 17:00 day), and there is no overlap with New York, so someone has to stretch their hours. Rotating the inconvenient time among teams is fairer than always asking one side to meet late at night.
Asynchronous communication and recorded meetings reduce the need for impossible overlaps.
DST Traps
The US and Europe change their clocks on different dates, so the offset between New York and London is 4 hours for a few weeks each year instead of 5. Sydney changes in the opposite season. A recurring meeting that is fine in one month can shift an hour for some participants. Check recurring invitations after each change, and use calendar tools that handle time zones. Always put the city and date next to a time when you write an invitation, such as 'Tuesday, Nov 10, 14:00 UTC / 9:00 a.m. New York'.
Etiquette and Practicality
Share a time zone link or the UTC time in invitations. Avoid scheduling meetings at times that are late at night or before dawn for large groups. Ask people for their preferred hours. Keep a simple team chart showing local times and working hours. Respect holidays and weekends in different countries, which fall on different days: Friday is a weekend day in some Middle Eastern countries.
Frequently Asked Questions
How do I convert between time zones?
Subtract the source zone's UTC offset to get UTC, then add the target zone's offset.
What time is 9 a.m. New York in Tokyo?
In winter (UTC−5), it is 11:00 p.m. the same day in Tokyo (UTC+9).
Does India observe daylight saving?
No. India stays on UTC+5:30 all year.
Why does the New York-London difference change?
Because the US and Europe switch to daylight saving on different dates.
How can I find a good meeting time for several zones?
Convert working hours to UTC and look for overlaps, rotating inconvenient times fairly.