Time Zone Meeting Planner

Add the cities you need on a call, pick the date, and this shows all 24 hours as a grid with each city’s local time. Where every city is inside its working hours, the column is highlighted — that band is your meeting window, and if there isn’t one the tool says so plainly.

How to use it

1. Pick a city from the list and press Add. Repeat for up to eight cities.
2. Set the date you are planning for. This matters more than it looks.
3. Adjust the working window if your team does not run nine to five.
4. Read the highlighted band. The summary line gives the earliest start that works for everyone.
5. Copy the invite line and paste it into your message, so nobody has to convert anything themselves.

The two weeks a year when your recurring call is wrong

Here is the thing that catches out even experienced remote teams, and the reason this planner recalculates offsets for a specific date rather than storing a fixed difference.

Time zone offsets are not properties of places. They are properties of places at moments. London and New York are five hours apart for most of the year, and any number of tools will tell you that as though it were a fact about the two cities. It is not.

The United States moves to daylight saving on the second Sunday in March. The European Union moves on the last Sunday in March. For the two or three weeks between those dates, New York has sprung forward and London has not, so the gap is four hours instead of five. In autumn the same thing happens in reverse: the EU falls back on the last Sunday in October, the US on the first Sunday in November, giving a week at four hours again.

A 3pm London call that normally lands at 10am in New York becomes an 11am call for a fortnight. If it was scheduled as “3pm London” in a calendar with proper timezone handling, the New York attendee sees the shift and copes. If someone wrote it down as “10am ET” in a recurring invite, half the team turns up an hour out.

It gets worse with cities that never change clocks. India stays at UTC+5:30 all year, so its gap to London swings between 4:30 and 5:30 twice annually without anything happening in India at all. Arizona does not observe daylight saving while the rest of Mountain Time does. Queensland does not while New South Wales does, which means Brisbane and Sydney — same country, adjacent states — are sometimes the same time and sometimes an hour apart.

This tool computes each city’s offset for the exact date you select, using the timezone database already inside your browser, and it warns you when any city on your list changes clocks within two weeks either side of that date. That warning is the whole point: it tells you when a slot that works today will not work next month.

What it does not do

It plans against working hours, not against real calendars — it has no idea whether anyone is actually free. Public holidays are not included, and they vary by country and sometimes by region. The city list is curated to around forty-five entries rather than the full IANA database of nearly six hundred, so an unlisted city needs substituting with one in the same zone. It also assumes one continuous working window per city, which does not model a long lunch break or a split shift.

Nothing is uploaded. Everything is computed locally, and the shareable link encodes your city list in the URL.

Common offsets, and how they move

City	Standard	Daylight saving	Observes DST
London	UTC+0	UTC+1	Yes
Berlin	UTC+1	UTC+2	Yes
Dubai	UTC+4	—	No
Delhi	UTC+5:30	—	No
Singapore	UTC+8	—	No
Tokyo	UTC+9	—	No
Sydney	UTC+10	UTC+11	Yes
New York	UTC−5	UTC−4	Yes
Chicago	UTC−6	UTC−5	Yes
Phoenix	UTC−7	—	No
Los Angeles	UTC−8	UTC−7	Yes

Realistic overlap, nine to five

Pair	Overlapping hours
London – Berlin	7
London – New York	3
London – Delhi	4
London – Singapore	1
New York – Los Angeles	5
New York – Singapore	0
London – Sydney	0