Time Zone Converter

Use this Time Zone Converter to translate a specific local date and time between worldwide IANA time zones.

Result

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Mobile, tablet or desktop

How to Use the Time Zone Converter

Search or type a source and destination IANA identifier, such as America/New_York or Asia/Tokyo. Enter a date and 24-hour time. If the source clock repeats during a backward change, explicitly choose its earlier or later occurrence. Skipped source times are rejected. Swap uses the converted time as the new source, preserving the instant when a result is available.

Formula and Explanation

UTC instant = source local clock − source zone offset at that instant
Destination local clock = UTC instant + destination zone offset
Clock difference = destination offset − source offset

IANA zones represent regional clock rules, not permanent offsets. Browser-native Intl supplies the installed time-zone data. The converter searches for actual instants that reproduce the entered local time; none means a skipped time, while two means an ambiguous repeated time. UTC offsets and the difference are evaluated at the selected instant. A day-change label compares destination and source calendar dates.

Supported input dates are 1970–2100. Accuracy follows the browser’s installed IANA/ICU data; governments can change future rules. Update your browser and confirm critical schedules. Abbreviations such as CST are ambiguous; use IANA names. No fixed-offset assumptions, leap-second scheduling or travel itinerary service is provided.

Worked Example

On 2026-07-01 at 12:00 in America/New_York, the instant is 16:00 UTC and 01:00 on July 2 in Asia/Tokyo: Tokyo is 13 hours ahead and the date is the next day. On 2026-11-01 at 01:30 in New York, the earlier occurrence is 05:30 UTC and the later is 06:30 UTC.

Frequently Asked Questions

Why can a local time be rejected?

A clock change can skip a local interval. For example, New York 2026-03-08 02:30 never occurs. Choose an existing local time rather than assuming an offset.

What are earlier and later occurrences?

When clocks move backward, the same local clock reading may occur twice. Earlier selects the first UTC instant and later the second. The default requires an explicit decision for repeated source times.

Does the difference stay the same all year?

Not necessarily. Source and destination regions may change clocks on different dates, or only one may observe DST. The displayed difference applies to the selected instant.

Can I use zones outside the suggested list?

Yes. Type any IANA zone identifier supported by your browser. Suggestions use Intl’s available zone list plus common US zones and UTC. Invalid identifiers produce an error.