タイムゾーン変換

What this tool does

Show one clock time in a source time zone and the same instant in a target time zone.

How to use

1. Enter the date and time.
2. Choose the source and target time zones.
3. Press Convert.

Examples

• New York to London in June

  15 June 2024 at 12:00 in New York is 17:00 in London. New York is UTC-04:00 and London is UTC+01:00 on that date.

Main features

• Source and target date and time.
• UTC offset for each zone on that date.
• A note when a fall-back hour happens twice.

How it works

The page finds the instant that matches the local date and time in the source zone, then formats that same instant in the target zone. Offsets come from the browser time-zone data for that date, so daylight-saving rules are included.

Tips

• A time that does not exist when clocks spring forward is rejected.
• When clocks fall back, the earlier of the two instants is shown and labeled.

Limitations

The list is the set of time zones the browser provides. The page does not call a time-zone service.

See the disclaimer for what these tools do not cover.

FAQ

How does the time zone converter work?

It keeps one instant and shows that instant's clock time and UTC offset in each zone you choose.

Does it use my computer's time zone?

No. The result uses the source and target zones you select.

What happens during a spring-forward gap?

A local time that does not exist is rejected instead of being shown as a normal conversion.

What happens when clocks fall back?

The local time happens twice. The page uses the earlier instant and says so.

Can the date change?

Yes. A conversion across the date line can show the previous or next calendar day.

Are these numbers sent to a server?

No. The clock time and the two zones are converted in this tab. They are not sent to a server.