Not every zone sits on a whole UTC hour. This pair shows why a comparer must preserve minutes and then check seasonal rules independently.
Winter: ten hours and thirty minutes
In a typical Northern Hemisphere winter, America/New_York uses UTC−5 and Asia/Kolkata uses UTC+5:30. Delhi is therefore ten hours and thirty minutes ahead. At 08:00 in New York, the same instant is 18:30 in Delhi. The destination minutes are not zero, so presenting only a rounded hour difference would produce the wrong meeting time.
Summer: nine hours and thirty minutes
During New York daylight time, its offset normally becomes UTC−4 while Delhi remains at UTC+5:30. The gap narrows to nine hours and thirty minutes. At 08:00 in New York, Delhi reads 17:30. India’s zone did not change; the seasonal movement happened only in New York, and the comparison reflects that selected instant.
Use the 24-hour view for a call
A large difference leaves a narrow overlap between ordinary waking hours. Instead of repeatedly adding nine and a half or ten and a half hours, scan the mapping produced for the selected date. The highlighted cells show where both local clocks fall between 08:00 and 19:59. They are suggestions, not claims about anyone’s actual work schedule or availability.