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Time Zone Converter

See one moment in time across multiple time zones at once, with offsets and day shifts.

The time above is read in the source zone. Nothing leaves your browser.

Target time zones

Converted times

Pick a date and source zone to convert.

How to convert time between time zones

  1. Set the date and time

    The tool starts at the current moment in your own zone. Pick any other date and time to convert instead.

  2. Choose the source zone

    Type a city or region into the source field to tell the tool which zone the time above is written in.

  3. Add target zones

    Add as many zones as you need; five common ones are preloaded and each row has a remove button.

  4. Read the converted times

    Every row shows the time, date, UTC offset, and a day-shift tag. Click Copy all times to export the list as text.

Why use this tool

Complete IANA zone list

The pickers cover every time zone your browser knows, typically 400 plus, all searchable by typing.

Unlimited target zones

Compare one instant across as many places as needed; UTC, New York, Los Angeles, London, and Tokyo start preloaded and any row can be removed.

Daylight saving done right

Offsets are resolved for the exact date chosen, so a January meeting and a July meeting each convert with the correct seasonal offset.

Day-shift tags

Rows landing on a different calendar day carry a +1 day or -1 day marker, preventing date-line scheduling mistakes.

One-click plain-text export

Copy all times outputs each zone with its date, time, and UTC offset, ready for an email or chat.

Private by design

Meeting times and zones are computed in the page and never sent to a server.

About this tool

This time zone converter takes one wall-clock moment, a date and time read in a source zone you choose, and re-displays it in any number of target zones at once. The zone list covers every IANA time zone your browser ships, usually more than 400. Conversions resolve the UTC offset for the specific instant you choose, so daylight saving transitions are applied correctly on either side of the change. Each row shows the local time, the full date, the UTC offset, and a +1 day or -1 day tag whenever the calendar date differs from the source.

The obvious job is scheduling: finding a call slot that lands inside working hours for offices in, say, London, New York, and Tokyo, or publishing an event time that readers in several regions can trust. The day-shift tags earn their keep around the international date line, where a Friday afternoon in San Francisco is already Saturday in Auckland. The Copy all times button turns the whole comparison into plain text for a calendar invite or a chat message.

Since the converter relies on the time zone database built into your browser, nothing you schedule is uploaded anywhere. For timestamps that arrive as raw epoch numbers in logs or APIs, decode them first with the Unix timestamp converter; for recurring schedules rather than single moments, the cron parser previews run times in local time or UTC.

Frequently asked questions

How does the time zone converter work?
Choose a date and time and the time zone it is in. The tool treats that as a single instant and re-displays it in every target zone you add, so you can read off the matching local time in each place at once.
Which time zones are supported?
All IANA time zones your browser knows about, which is typically 400 or more, covering every region from America/New_York to Asia/Kolkata. Start typing a city or region to filter the list.
Does it handle daylight saving time?
Yes. Conversions apply the correct daylight saving offset for the specific date you pick, so a summer meeting and a winter meeting convert correctly even when the offset changes.
What do the +1 day and -1 day labels mean?
When the converted time lands on a different calendar day than your source time, the row is tagged +1 day or -1 day so you do not accidentally schedule a call for the wrong date across the international date line.
Is my schedule data private?
Completely. The converter runs only in your browser, using the time zone database built into it. No times, zones, or meeting details are uploaded or stored.

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