How are the time zones calculated?

The clock uses your browser's built-in IANA time-zone database via the Intl API — the same data your operating system uses. This means daylight-saving transitions are applied automatically and correctly for each city.

How accurate are the times?

The displayed times are as accurate as your device's own clock, ticking once per second. UTC offsets and the difference versus your local zone are computed live, so they update if a city crosses a daylight-saving boundary.

How do I find the time difference between two cities?

Add both cities and read the "ahead of or behind your time" figure for each. Subtract those two values to get the difference between the cities — for example, a city at +5 and one at -3 are 8 hours apart.

Can I switch between 12-hour and 24-hour time?

Yes. Toggle 12-hour mode for AM and PM display, or leave it off for 24-hour time. The setting applies to every city in your list at once.

Does it adjust for daylight saving time automatically?

Yes. Because it relies on the IANA database, each city follows its own daylight-saving rules, so the times stay correct across spring-forward and fall-back transitions without any manual change.

Why is the time difference to a city not a whole number?

Some zones use 30 or 45 minute offsets — India is UTC+5:30 and Nepal is UTC+5:45 — so the difference from your zone can include half or quarter hours.

Is any location or clock data sent to a server?

No. Nothing is fetched and no location is shared — all time-zone conversions run locally in your browser using built-in browser data, so the tool works offline and keeps your activity private.

World Clock — Multiple Cities

Multi-city world clock

This multi-city world clock shows the live time and date in cities around the globe, side by side. Add the places you care about and each appears with its UTC offset and how many hours it is ahead of or behind your own device. It is ideal for scheduling international calls, coordinating remote teams, and tracking markets or family abroad.

How it works

The clock reads your device’s current time once per second and converts it into each city’s local time using your browser’s built-in IANA time-zone database through the Intl API — the same data your operating system uses. Because each city carries its own daylight-saving rules, transitions are applied automatically, and offsets that aren’t whole hours (like India at UTC+5:30) display correctly. The difference versus your own zone is computed live, so it stays right even when a city shifts for daylight saving.

Column	Meaning
Local time	Live time in that city
UTC offset	Hours ahead of or behind UTC
Vs your time	Hours ahead of or behind your device

Example

If your device is in London (UTC+1 in summer) and you add Tokyo (UTC+9), the row shows Tokyo as +8 hours. When it is 09:00 for you, Tokyo reads 17:00 — handy for finding a meeting slot that suits both.

It is privacy-first — no location is shared and no clock data is fetched; everything runs locally.