Time Zone Converter

Convert any date and time between world time zones instantly. Schedule meetings across continents, plan travel, and coordinate with global teams — with automatic daylight-saving adjustments and a multi-zone comparison table.

Date & Time (in source zone)

Source Time Zone

Target Time Zone

Swap

What is a Time Zone Converter?

A time zone converter translates a specific moment in time from one regional time zone to another. Although the underlying moment — the instant measured from UTC — is the same everywhere on Earth, local clocks display it differently depending on where you happen to be. The converter bridges that gap so you can communicate a single moment unambiguously to people in different regions.

Time zones were standardized in the late nineteenth century to resolve the chaos of every town keeping its own solar time. Today the world is divided into 24 nominal hourly zones, plus numerous offset zones at 30- and 45-minute intervals such as India (UTC+5:30) and Nepal (UTC+5:45). On top of this base structure, more than 70 countries observe daylight saving time, shifting their clocks forward in summer and back in winter according to local rules that differ by jurisdiction and occasionally change year to year.

Keeping all of this straight manually is virtually impossible. That is why this converter relies on the IANA time zone database, the de facto standard maintained by a global community of contributors and used by operating systems, programming languages, and cloud platforms worldwide. The database encodes every known historical, current, and planned time-zone rule, including DST transitions, so the conversions you see here match what your operating system and calendar apps display.

Common scenarios that call for a time zone converter include scheduling international meetings, planning multi-leg flights, coordinating live broadcasts, monitoring server logs across regions, attending virtual conferences, and staying in touch with friends and family abroad. Whether you are a remote worker, a frequent traveler, or a global project manager, having a reliable converter at hand eliminates the guesswork from cross-zone coordination.

How the Time Zone Converter Works

The converter leverages your browser's built-in Intl.DateTimeFormat API, which reads the IANA database shipped with your operating system. Internally, a JavaScript Date object always stores an absolute moment in UTC milliseconds; only the displayed string changes based on the requested time zone.

Conversion FormulaLocal Time = UTC + Time Zone Offset (offset includes DST when applicable)

When you enter a source datetime and source zone, the converter reconstructs the corresponding UTC instant, then formats that instant in the target zone. The multi-zone table repeats this formatting across ten major zones for at-a-glance comparison. The time difference shown is the difference in offsets between source and target on that specific date — DST can change the gap by an hour between seasons.

Example

Given: Source = 9:00 AM on 15 June 2024 in New York (America/New_York, EDT = UTC−4).

UTC instant: 13:00 on 15 June 2024
Target = Tokyo (Asia/Tokyo, JST = UTC+9, no DST): 22:00 (10 PM) on 15 June 2024
Target = London (Europe/London, BST = UTC+1 in summer): 14:00 (2 PM) on 15 June 2024
Time difference New York → Tokyo: +13 hours

How to Use the Time Zone Converter

Enter the source date and time: Use the datetime picker to specify the moment you want to convert, expressed in the source zone.
Choose the source zone: Select the time zone in which the source datetime applies. This is usually the zone of the event organizer or the location where the meeting was originally announced.
Choose the target zone: Pick the zone you want to convert into. The swap button lets you quickly reverse source and target.
Click Convert Time: The result panel shows the source time and converted target time side by side, followed by a multi-zone comparison table for the same instant.
Review the offset summary: The line below the table reports the time difference between source and target zones, accounting for any DST in effect on the chosen date.

Tips for Scheduling Across Time Zones

Always State the Zone

When sending invitations, append the zone explicitly (for example, "3:00 PM IST"). This prevents recipients in other regions from misreading the time as their own local zone.

Watch DST Transitions

Daylight saving changes occur on different dates in different regions. A recurring meeting at 9 AM New York time may shift by an hour in your local zone when US clocks change but yours do not.

Use UTC for Global Teams

For documentation and server logs, express times in UTC. UTC never observes DST, so a timestamp is unambiguous regardless of the reader's location or the season.

Respect Working Hours

Before finalizing a meeting time, glance at the multi-zone table to confirm the chosen moment lands within reasonable working hours for all participants — ideally between 8 AM and 8 PM in each zone.

Frequently Asked Questions About Time Zone Conversion

How does the time zone converter work?

The converter uses your browser's native Intl.DateTimeFormat API, which knows the official IANA time zone database maintained by the Internet Assigned Numbers Authority. When you pick a source time, source zone, and target zone, the tool constructs a Date object and reformats it in the target zone, producing the correct local time including any daylight-saving adjustments.

Why do some times shift by an hour in summer?

That is daylight saving time (DST) in action. Regions that observe DST move their clocks forward by one hour in spring and back again in autumn. Because the IANA database tracks these rules per zone and per date, the converter automatically applies the correct offset for the specific date you choose, including the transitions themselves.

Which time zones are supported?

The dropdown includes the most commonly referenced zones worldwide, including UTC, GMT, Eastern (US), Central, Mountain, Pacific, India, Pakistan, Japan, China, Singapore, Australia Eastern, Central European, UK, and several others. The underlying API supports over 400 zones, so the same approach can be extended if you need additional options.

Is the converted time accurate for meetings and events?

Yes, provided the source datetime and source zone match the original invitation. Always confirm the source zone with the organizer, because invitations sometimes list a time in the organizer's local zone without explicitly labeling it. Once the source is correct, the target conversion is reliable down to the second and accounts for DST.

What is the difference between UTC and GMT?

UTC (Coordinated Universal Time) is the modern civil time standard maintained using atomic clocks, with leap seconds added as needed. GMT (Greenwich Mean Time) is the historical solar time at the Royal Observatory in Greenwich. For everyday purposes the two are equivalent, and the converter treats them as such, but UTC is the preferred scientific and engineering reference.

Can I convert to multiple time zones at once?

The primary output shows a single target zone of your choice, but the comparison table beneath it automatically lists the converted time across ten major zones worldwide. This makes it easy to pick a meeting slot that works for colleagues across regions, or to see at a glance how the chosen time lands in key business centers.

Time Zone Converter