Istanbul and Osaka Time Zone Comparison
The distance between Istanbul and Osaka is felt not just in kilometers, but in time zones too. Istanbul and Osaka sit on different continents, in noticeably different time zones, and neither observes daylight saving time.
Istanbul is always 6 hours behind Osaka, with no seasonal change, since neither city's daylight saving rules shift this relationship.
With a moderate gap like this, it's worth checking the suggested call window above before scheduling a meeting between Istanbul and Osaka.