Dates, zones, working hours, overlap calculations, and copied plans stay in your browser. The site may still send one anonymous tool-use total after successful planning.
How to Use the Time Zone Meeting Planner
- Choose the meeting date and local time in the base zone.
- Enter the base IANA zone and keep, replace, add, remove, or reorder comparison zones until two to six total zones are listed.
- Set the daily working-hour start and end used for every zone.
- Choose the first or second occurrence if a fall-back clock repeats the entered time, then select Plan meeting.
- Review local dates, offsets, overlap windows, and the scrollable timeline; select another timeline time or copy the summary or stable link.
How Date-Specific Time Zone and DST Conversion Works
An IANA identifier such as America/New_York or Asia/Kathmandu represents a location whose UTC offset can change by date. The planner asks the browser for the zone offsets near the entered local date, converts each candidate to a real UTC instant, and accepts only candidates that format back to the exact entered year, month, day, hour, and minute.
Most local times resolve to one instant. A spring-forward gap resolves to none and is rejected. A fall-back repeated time resolves to two, so the selected first or second occurrence determines the real instant. Every other displayed zone is then formatted from that same instant. The 48-column timeline covers 24 elapsed hours in half-hour steps, centered on the selected meeting.
Time Zone Meeting Examples
New York and London in January
On January 15, 2026, 9:00 AM in America/New_York is 2:00 PM in Europe/London and 11:00 PM in Asia/Tokyo. With 9:00 AM-5:00 PM configured hours, New York and London overlap then, while Tokyo is outside the highlighted interval.
The temporary US and Europe DST mismatch
On March 18, 2026, New York has already changed to daylight time while London has not. 9:00 AM in New York is therefore 1:00 PM in London for that date, not the January 2:00 PM conversion. Exact dates matter because regions change clocks on different schedules.
A 45-minute offset in Kathmandu
At 9:00 AM UTC, Asia/Kathmandu is 2:45 PM. Named zones and minute-accurate formatting avoid the incorrect whole-hour assumptions that fixed-offset mental math can introduce.
Working-Hour Overlap and Timeline Limits
A half-hour slot is a complete overlap only when its local clock time is at or after the configured start and before the configured end in every listed zone. These hours are one shared daily preference, not imported availability. The planner does not read calendars, public holidays, weekends, leave, local labor rules, or the intended meeting duration.
IANA rules change when governments change civil time, and browsers or operating systems distribute those updates on their own schedules. Recheck important future meetings after a legal time-zone announcement or software update. The timeline spans 24 real hours, so a displayed civil clock can skip or repeat an hour on a transition day.