Berlin is typically 8 hours behind Tokyo. When it's 5:00 PM in Tokyo, it's 9:00 AM in Berlin. Japan does not observe daylight saving time, while Germany does.
During Central European Summer Time (late March to late October), the difference is 7 hours. During CET (November to March), it's 8 hours.
Optimal meeting window: 8:00 AM - 10:00 AM Berlin time (4:00 PM - 6:00 PM Tokyo). This catches late afternoon in Tokyo while being morning in Berlin.
German automotive and engineering companies frequently coordinate with Japanese partners during these hours.