Meeting Time Zone Planner

You enter a date, a start time, and the base time zone that time is written in. The planner converts that wall-clock time to a single absolute instant in UTC, then renders that same instant in each participant zone. Because every zone shows the same moment, the local clocks line up exactly the way they would on the day of the call.

Yes. The conversion uses the time-zone database built into your browser and looks up each zone's offset at the exact meeting instant, so it applies the right rule for that date. A meeting in June and the same clock time in January can produce different offsets (for example New York is UTC-4 in summer and UTC-5 in winter), and the planner reflects that automatically.

Each participant's local meeting time is compared against a working window you set, which defaults to 9:00 AM to 5:00 PM. The window is half-open, so 9:00 AM counts as inside and 5:00 PM counts as outside. The overlap percentage is the share of zones that fall strictly inside that window, which tells you at a glance how many people are in comfortable hours.

Inside means the local time is within your working window. Edge means it is within one hour of the start or end, such as 8:15 AM or 5:30 PM, which is workable but not ideal. Outside means it is more than an hour beyond the window, which usually means early morning or late evening for that person.

Time zones far ahead of or behind the base zone can cross midnight relative to the meeting date. If a 7:00 PM call in New York lands at 9:30 AM the next morning in India, the planner labels that zone as the next day so you do not book someone a day off from where you think they are. It also shows the local weekday for the same reason.

The dropdown lists common business zones for quick selection, and you can add several participant zones to compare them side by side. All calculations run in your browser using the standard IANA time-zone data, so the offsets stay current with the rules your device already ships. Nothing you enter is sent anywhere.