LifeNaviHub

World Time & Working Hours Planner

Compare major-city clocks, convert local date-times, find common working hours, and shortlist meeting slots using IANA zones.

When remote teams need overlapping work windows or a fair meeting time.

Each city maps to an IANA zone; offsets and daylight saving come from Luxon/Intl. Multi-zone countries are never collapsed to one zone. Overlap and balanced meeting candidates (up to five) respect per-day DST. Clock precision depends on the browser/OS timezone database.

Displayed times depend on your browser/OS timezone database. Sub-second precision and future DST rule changes are not guaranteed.

Check this before you share a date and time

These four identical instants show when a Tokyo meeting time falls on the previous New York date, and when the working hours do not overlap. How a deadline lands in the recipient’s early morning is on the deadline page.

  1. Do not share a time like “2026-01-15 09:00” without the city and time zone. It can be the previous day for the other person. In New York that is 2026-01-14 19:00 (UTC−05:00) in winter and 2026-07-14 20:00 (UTC−04:00) in summer.
  2. On these four instants Tokyo stays UTC+09:00. New York is UTC−05:00 in winter and UTC−04:00 in summer. Do not reuse one fixed difference for every conversion that year.
  3. On the invitation, write both local dates and times and the IANA zones. Add UTC when that also helps.
  4. On these two dates, 09:00–18:00 on both sides has no shared working time. Say that there is no shared working time, and consider an async reply or moving the hours. Hours and holidays differ by organization, so do not read this example as a general rule.

The figures are conversions from the same IANA data (Luxon) this site already uses for World Time. They are not a copy of a government notice.

A local time that does not exist, or that happens twice, is on the clock-change decision page

See where a deadline lands in the deadline planner

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