Plainwren

Time zone meeting planner

Add the cities of everyone in the meeting and pick a date. The grid shows each local time hour by hour, shades working hours, and lists the windows when everyone is at work. Click a time to get a line to paste into a chat, a calendar file, or a link to share these settings.

Cities or time zones (2 to 6)

How it works

  1. The day comes from zone 1. The grid covers the chosen date from midnight to midnight in the first zone. On the day its clocks change, that day has 23 or 25 hours, and the grid shows exactly that many rows.
  2. Each row is one real hour. For every hour, the planner takes the exact moment and shows the wall-clock time in each zone, using your browser's built-in time zone database. Daylight saving is applied for that exact date in every zone, so zones that change on different dates are handled correctly.
  3. Working hours are local times for each person (9:00 to 18:00 unless you change them). An end time earlier than the start, such as 22:00 to 06:00, means a night shift. A cell is shaded only if the whole hour is inside working hours.
  4. Overlap windows are found by checking every 15 minutes, so zones with 30- or 45-minute offsets, like India (UTC+05:30) or Nepal (UTC+05:45), give exact windows such as 13:00–16:30. Windows shorter than your meeting length are not listed.
  5. Nothing is sent anywhere. The calendar file is made on your device, and the share link stores the settings in the address itself, for example ?z=Asia%2FDubai~0900-1800,Europe%2FLondon~0900-1800&d=2026-11-03.

Worked example

Dubai, London and Mumbai, all working 9:00 to 18:00, on Tuesday 3 November 2026. That day Dubai is UTC+04:00, London UTC+00:00 (summer time ended on 25 October) and Mumbai UTC+05:30.

  • London's 9:00–18:00 is 13:00–22:00 in Dubai. Mumbai's 9:00–18:00 is 07:30–16:30 in Dubai.
  • All three overlap from 13:00 to 16:30 Dubai time (09:00–12:30 London, 14:30–18:00 Mumbai): a 3.5-hour window.
  • Choosing 13:00 for 30 minutes gives: Tue 3 Nov 2026: Dubai 13:00–13:30 (UTC+04:00) · London Tue 3 Nov 09:00–09:30 (UTC+00:00) · Kolkata Tue 3 Nov 14:30–15:00 (UTC+05:30). Mumbai shows as Kolkata, the name of its official time zone.

The same three cities on Friday 2 October 2026, when London is on summer time (UTC+01:00), overlap from 12:00 to 16:30 Dubai time. Add New York to the November plan and there is no time when all four are at work: 13:00–16:00 Dubai is the best, with 3 of 4 people in working hours.

Daylight saving traps the planner handles

  • Different change dates. Europe changes on the last Sundays of March and October; the US and Canada on the second Sunday of March and the first Sunday of November. For a few weeks each spring and autumn the London–New York gap is 4 hours, not 5.
  • Southern hemisphere. Places such as Sydney, Adelaide and Auckland move their clocks forward around October and back around April, the opposite of Europe and North America.
  • Half- and quarter-hour zones. Adelaide is UTC+09:30 (+10:30 in summer), Newfoundland UTC−03:30 (−02:30 in summer), Nepal UTC+05:45 and the Chatham Islands UTC+12:45 (+13:45 in summer).
  • Different days. A morning call in New York is already the next day in Auckland. The grid shows the day name whenever a zone is on a different date from zone 1.

FAQ

My city is not in the list. What do I type?

Time zones are named after one major city each (for example Asia/Kolkata covers all of India). Type a nearby big city or the country's main zone. Many common cities, such as Mumbai, San Francisco and Abu Dhabi, are recognised directly.

Does it know about public holidays or weekends?

No. It knows time zones and the working hours you enter, not calendars. The grid shows day names where they differ, so check that the time is not on someone's weekend (Friday and Saturday or Saturday and Sunday, depending on the country) or a holiday.

Will the calendar invite be in the right time zone?

Yes. The .ics file stores the meeting in UTC, and calendar apps such as Google Calendar, Outlook and Apple Calendar show it in each person's own time zone. It is a single event, not an invitation: import it, then invite people from your calendar.

What happens if a government changes its time zone rules?

The planner uses the time zone data that comes with your browser, which is updated with browser updates. For a date far in the future, rules may change before then, so check again nearer the time.

Is the share link private?

The link contains only the zones, working hours, date, length and title, in the address itself. Anyone you send it to can see those settings. Nothing is stored on a server, but like any web address it can appear in browser history and the site's hosting logs, so do not put anything secret in the title.