Time Zone Converter
Pick a time in one place and read it everywhere else. Set the date too — half the world moves its clocks twice a year, and not on the same weekend.
Runs on your device — nothing you type is sent anywhereThe date matters as much as the hour. Clocks move twice a year, and not on the same weekend everywhere.
The zone rules come from your own browser, which carries the standard database and updates it with the browser. A very old device may not know about a change made in the last year or two.
How it works
Three steps, and the zone rules come from your own browser.
Say when, and where
A time, a date, and the place that time is in. It starts on your own zone and the time right now.
Add the other places
As many as you need. They stay while you change the time, so you can drag a meeting around and watch all of them move.
Read the warnings as well as the hour
A row that lands on a different date says so — and if that country moves its clocks within a month of the date you picked, the row tells you when.
When this comes up
Booking a call across countries
The hour is the easy part. The trap is the stretch in spring or autumn when one country has moved its clocks and the other has not yet.
Working with a team in several places
Add all of them once and the whole list moves together as you try different times, instead of doing the arithmetic five times.
Catching something live
A match, a launch, a broadcast, an exam result. Announced in one zone and watched in another.
Family somewhere else
Whether it is a reasonable hour to ring, without waking anyone to find out.
The part other converters leave out
Converting a time between two places sounds like subtraction, and for most of the year it is. The reason it goes wrong is that the number you subtract is not a property of the place. It is a property of the place on that date.
Nine in the morning in New York is two different times
In January, New York is five hours behind UTC. In July it is four. Same city, same clock on the wall, an hour of difference to everybody else in the world.
Now put a second city on the other side of it. The gap between London and New York is five hours for most of the year — but for two or three weeks in March, and a week in the autumn, the two have moved their clocks on different weekends and the gap is four. Measured across 2025, 2026 and 2027 that spring window is 21, 21 and 14 days. A meeting agreed in February for a date in late March is exactly how people end up on a call an hour early, or an hour late, with everyone certain they did the sum right.
They did do the sum right. The sum changed.
This page asks for the date for that reason. And when a country is about to move its clocks — within a month of the date you are asking about — the row for it says so, and on which day. That is the warning that stops the mistake, because it arrives while you are still choosing the date.
Where the rules come from
Nothing on this page is a list we typed in. Your browser carries the standard time zone database — every zone, every daylight saving rule, and every historical change to one — and it ships updates with the browser itself.
That matters more than it sounds, because these rules change by government decision, several times a year, somewhere in the world. A page with its own table of offsets is wrong within months and has no way of knowing. This one is as current as the browser you are reading it in.
Why the southern hemisphere makes it worse
Daylight saving runs in opposite directions either side of the equator. When Europe springs forward, Australia is falling back. So the gap between London and Sydney does not shift by an hour twice a year — it shifts by two hours, four times a year, and spends a few weeks at values it holds at no other point.
And a large part of the world does not observe it at all: most of Asia, most of Africa, and a good deal of South America. Those places keep a constant offset while everyone around them moves, so a stable relationship with one partner and a shifting one with another is entirely normal.
The names are places, not countries
Zones are named after a city rather than a country because countries are not the unit. The United States has six. Australia has several and they disagree about daylight saving internally. Meanwhile the whole of China runs on one, and India is offset by half an hour rather than a whole one — as are parts of Australia, and Nepal by three quarters.
So pick the city, not the flag. It is the only thing that unambiguously identifies which set of rules applies.
Nothing you type is sent anywhere
It is arithmetic and a lookup, both of which happen in your browser. There is nothing to transmit, no account and nothing stored — the same as everything else here.
Common questions
How do I convert a time between two time zones?
Set the time and the date, choose the place that time is in, and add the other places you care about. Each row shows the local time there, the date if it lands on a different day, and a warning if that country moves its clocks within a month of the date you picked. The zone rules come from your own browser, so they are as current as it is.
Why does the date change the answer?
Because the offset is a property of the place on that date, not of the place. New York is five hours behind UTC in January and four in July. For two or three weeks each March, Europe and North America have moved their clocks on different weekends, so the usual gap between London and New York is an hour smaller than everybody remembers.
Does this handle daylight saving automatically?
Yes, and rather than doing it silently it tells you when the clocks are about to move. The calculation uses your browser’s copy of the standard time zone database, which knows every daylight saving rule and every historical change to one, so a date in the past converts using the rules that applied then, not today’s.
Why are time zones named after cities?
Because countries are not the unit. The United States has six zones, Australia has several that disagree internally about daylight saving, and the whole of China runs on one. A city name identifies exactly one set of rules, which a country name often does not.
Why is the difference to Australia not a whole number of hours?
Partly because several zones are offset by half an hour or three quarters rather than a whole one — parts of Australia, all of India, and Nepal. And partly because daylight saving runs in opposite directions either side of the equator, so the gap between Europe and Australia shifts twice a year in each direction rather than once.
Do I need an account?
No, and there is nothing to store. The whole thing is a lookup and some arithmetic running in your browser, with nothing transmitted at any point.
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Every one of them runs on your device. No uploads, no accounts.