Scheduling a meeting across two time zones is manageable with basic mental math, but add a third or fourth region and it quickly becomes genuinely hard to hold in your head, especially once daylight saving time means the offsets between regions aren't even fixed year-round. The practical fix isn't better mental math, it's a different approach to the problem entirely: convert everyone to a shared reference and find the overlap visually instead of converting pairwise.
Why pairwise conversion breaks down past two people
With two participants, converting one person's proposed time into the other's local time is a single subtraction using the Timezone Calculator, manageable even by hand. With four or five participants across different regions, though, you'd need to run that same conversion for every pair, and worse, a time that works for two of them might turn out to be the middle of the night for a third, information that pairwise conversion doesn't surface until you specifically check for it. The number of pairwise checks grows fast as more people are added, which is exactly the kind of problem that's easy to get subtly wrong by hand.
The anchor-and-overlap approach
A more reliable method is to list every participant's time zone against a single shared reference (often UTC), lay out each person's reasonable working hours (say, 9 AM to 6 PM local) translated into that shared reference, and look for a window where all of those ranges overlap. This turns the problem from a series of separate pairwise conversions into a single visual comparison, an overlap either exists in the combined range or it doesn't, and if it doesn't, you can immediately see which participant's hours are the constraint forcing an early-morning or late-evening compromise. The Meeting Time Planner is built specifically around this approach, showing each participant's local time and working-hours window side by side so the workable overlap (if one exists) is immediately visible.
Daylight saving makes this a moving target
A meeting time that works well in January can shift by an hour relative to some participants by July, if any of the involved regions observe daylight saving time and others don't, or if they switch on different calendar dates, a problem explained in more depth in our guide on how time zone conversion actually works. For a recurring meeting spanning a DST transition, it's worth rechecking the overlap after the switch rather than assuming the original time still works for everyone.