How to use this calculator
The meeting planner searches for a time that fits the working windows of people in different time zones. Enter the participants’ locations, available weekdays, and local windows, then choose the meeting duration and search dates. The results identify slots long enough for the whole meeting rather than merely finding a moment when everyone is briefly available.
This is a planning tool for availability rules you enter. It does not connect to personal calendars or know about appointments, leave, or last-minute changes. Once you find a suitable result, check its local date and time for each participant and confirm it with the people involved. For recurring meetings, review later occurrences because seasonal clock changes can shift local times.
Formula and calculation method
Eligible meeting slots = intersection of all participant availability windows, with at least the requested elapsed duration remaining.
Convert availability to comparable instants
Each person’s local working window is interpreted in that person’s zone for the date being searched. The planner can then compare all windows on one timeline. A window described as 09:00–17:00 is not assumed to have the same UTC position in every location or throughout the year.
Require the complete duration
A proposed start qualifies only if the whole meeting fits the shared window. A 60-minute meeting cannot start 30 minutes before someone’s availability ends. This prevents a common planning mistake in which the start looks acceptable but the meeting finishes outside a participant’s working hours. Review the end as carefully as the start.
Worked examples
An hour inside a two-hour overlap
Suppose the entered windows overlap from 14:00 to 16:00 UTC. A one-hour meeting beginning at 14:00 fits, and so does one beginning at 15:00. A start at 15:30 does not fit because the final 30 minutes would fall outside the shared window. The exact offered slots follow the planner’s search grid.
No match for a longer meeting
If the shared availability is only 30 minutes but the requested duration is 60 minutes, there is no valid slot. Shortening the meeting or widening someone’s stated window can create a match. A no-result message therefore does not mean the locations never overlap; it may mean the requested duration is too long.
A recurring meeting across a clock change
A weekly meeting anchored at a fixed local time in one location can move by an hour for a participant whose region changes clocks on a different date. Inspect the later-week preview instead of copying the first week’s local readings to every occurrence. The anchor determines which local time stays fixed.
Edge cases and practical checks
Availability is supplied, not discovered
The planner sees only the windows you enter. It cannot detect a calendar conflict, holiday, or personal preference that is absent from those inputs. Treat a suggested slot as a candidate, and verify exceptions before sending an invitation. A short test range is useful for checking that each participant’s weekday settings are correct.
Search horizon and recurring assumptions
The search is limited to 14 days. Later-week previews help expose offset changes but do not guarantee that participants remain available indefinitely. Future conversions depend on installed time-zone rules. For recurring events, preserve the intended anchor location and recheck any date on which local rules or schedules change.
Frequently asked questions
Does this read my calendar?
No. It searches the availability windows entered on the page. Existing meetings and private events are not imported. Confirm a suggested time against the participants’ actual calendars before treating it as a booked appointment or a guaranteed free slot.
Why are there no matching times?
The windows may not overlap long enough for the requested duration, or the selected weekdays may not align. Check each location and local window, shorten the meeting if appropriate, and search another date. A seasonal clock change can also affect the overlap during a particular week.
Does everyone need to be free for the full meeting?
Yes. The full duration must fit inside the intersection of the entered windows. An overlap at the starting minute alone is insufficient. This is particularly important for longer meetings that approach lunch breaks or the end of someone’s workday.
Will a weekly meeting keep the same local time everywhere?
Not always. A recurring series anchored to one location can shift in another location when their offsets change differently. Review the recurrence preview and communicate any changed dates explicitly. A fixed UTC series and a fixed local-time series are different scheduling choices.
Can I search months ahead?
The search covers up to 14 days from the chosen starting date. You can move that starting date to inspect another period. Far-future results still depend on available time-zone rules and the assumption that the entered working windows remain valid.
What should I check before sending an invitation?
Confirm the selected slot’s date, start, end, and location for every participant. Check actual calendar conflicts and any exceptions missing from the entered windows. For a repeating meeting, review the anchor and later occurrences rather than assuming the first conversion applies forever.
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