How does the meeting planner handle daylight saving time?

It converts the selected date with Intl.DateTimeFormat and the named IANA zones supported by the visitor's browser, so the offset is date-specific rather than fixed.

Does TimeZoneCentral store meeting details?

The calculations run in the browser. Shared links put only the selected date, time and zone identifiers in a URL fragment, which is not sent in the HTTP request; no names, email addresses or meeting titles are requested.

Time Zone Central

Time Zone Meeting Planner

Pick an exact local date and time, compare it across up to six zones, and find a slot that lands inside more working days. No signup.

1. Set the reference time

Date Time Reference zone

Offsets are calculated for the selected date. Times inside a daylight-saving gap are rejected instead of silently shifted.

2. Choose comparison zones

3. Compare the local times

Working-hour timeline

Each row shows the local hour for the same 24 candidate instants. Green marks 09:00–16:59; amber marks 07:00–08:59 and 17:00–19:59. Select a column to use it.

How the conversion works

TimezoneCentral converts one instant using named zones such as Europe/Paris and America/New_York. Unlike a fixed UTC offset, a named zone can apply the daylight-saving rule that belongs to the selected date.

The calculation uses Intl.DateTimeFormat and the time-zone data installed in your browser. Those rules are generally distributed from the IANA Time Zone Database, which changes when governments alter civil-time rules. Keep your browser current and recheck important future meetings after a rule change.

All calculations happen on this page. The planner asks only for a date, a time and zone identifiers. A shared link stores those values after the # as a URL fragment, which browsers do not send in the HTTP request. If you accept analytics, the configured page location also excludes URL parameters.

Meeting planner questions

How does it handle daylight saving time?

It resolves the chosen date through each named IANA zone supported by your browser. The displayed offset therefore changes with that date instead of assuming today’s offset.

What happens to a nonexistent or repeated local time?

A local time skipped during a spring-forward transition is rejected. If a fall-back transition repeats the same clock time, the planner uses the earlier matching instant and tells you that the time is ambiguous.

Are working hours a scheduling guarantee?

No. The color guide uses 09:00–17:00 as a neutral default and does not know a participant’s availability, holidays or preferences. Confirm the proposed time with everyone.