Istanbul and Karachi Time Zone Comparison
Istanbul and Karachi are two major cities that sit in noticeably different time zones. Istanbul and Karachi sit on different continents, in noticeably different time zones, and neither observes daylight saving time.
Istanbul is always 2 hours behind Karachi, with no seasonal change, since neither city's daylight saving rules shift this relationship.
With such a small gap, scheduling a call between Istanbul and Karachi is easy — a normal business-hours slot works for both sides on the same calendar day.