Time Zone Converter

What is the Time Zone Converter?

The Time Zone Converter takes one moment in time — a date and a clock time in a source time zone — and shows you what that same instant looks like in one or more other time zones. Unlike a simple "what time is it there" clock, this tool is built for the harder question: if it is 3:00 PM here on this date, what time is it for everyone else? You can stack several target zones at once, so a single source time produces a full side-by-side view of local times. It is the fastest way to settle the time difference between cities without doing UTC math in your head.

How to use it

1. Set the source. By default the source zone is your own time zone and the time is set to right now. Change either if you want to convert from somewhere else (for example, a colleague's city).
2. Pick the date and time you want to convert. The date matters — it decides whether Daylight Saving Time is in effect.
3. Add your target zones. Choose an IANA zone for each one and add as many as you need; each appears as its own row.
4. Read the result instantly. Every target shows its converted local date/time and how far ahead or behind it is from the source. No button to press, no page reload — you get the answer and move on.

The method behind it

A time zone is really just an offset from Coordinated Universal Time (UTC), but that offset is not constant: many regions shift by one hour during Daylight Saving Time. The naive approach — "London is UTC+0, New York is UTC-5, so subtract 5" — breaks the moment DST starts or ends, and the two regions don't even switch on the same day. This converter avoids that trap entirely. It builds the exact instant you selected, then asks the browser's native Intl date engine to render that instant in each target zone. Because Intl ships with a maintained IANA time-zone database, the correct DST rule for that specific date is applied automatically — there is no offset table to go stale. The difference between two zones is computed from each zone's actual offset on the chosen date, so the number you see is always the real gap, DST included.

Examples

• 3:00 PM London → New York and Tokyo (a July date). London is on summer time (BST, UTC+1) and New York is on EDT (UTC-4), so 3:00 PM London becomes 10:00 AM in New York (5 hours behind). Tokyo, which has no DST, shows 11:00 PM the same day (8 hours ahead).
• 9:00 AM Los Angeles → London (a January date). In winter both sides are on standard time: Los Angeles is PST (UTC-8) and London is GMT (UTC+0), an 8-hour gap, so 9:00 AM in LA is 5:00 PM in London.
• EST to PST. 2:00 PM in New York (Eastern) converts to 11:00 AM in Los Angeles (Pacific) — a steady 3-hour difference that holds in both standard and daylight periods because both zones shift together.

Common use cases

• Scheduling a recurring video call for a remote team spread across continents.
• Booking a flight or phone interview and confirming the local time on both ends.
• Watching a live event (sports, product launch, broadcast) announced in a different country's time.
• Coordinating with family or friends abroad without waking anyone at 3 AM.
• Planning trading, deadlines, or release windows around a foreign market's business hours.

Why use this one

Most converters answer one zone at a time, forcing you to run the same lookup over and over for each person on a call. The whole idea is to see one source time in many target zones at once, on a single screen — ideal for planning a cross-time-zone meeting in one glance. It supports every IANA zone (not a short preset list), gets DST right for the exact date you pick, requires no sign-up, and runs entirely in your browser, so your dates and times never leave your device.

It is also part of a small, focused clock toolkit. If you just want the current time in several cities ticking live, the World Clock shows them all at once. To translate machine timestamps, the Unix Timestamp Converter turns epoch seconds into readable dates in any zone. And to track the gap to a future moment, the Countdown Timer counts it down for you.

Frequently asked questions