Shanghai is 15 hours ahead of San Diego

Best overlap: 5:00 PM to 6:00 PM in San Diego is 8:00 AM to 9:00 AM in Shanghai.

San Diego and Shanghai overlap from 5:00 PM to 6:00 PM (San Diego) to the equivalent 8:00 AM to 9:00 AM in Shanghai — that's your meeting window. You've got roughly 1 hour — enough for a focused daily check-in if you hold it at 5:00 PM in San Diego (8:00 AM in Shanghai). Note the day shift — Shanghai is on the next day relative to San Diego while this overlap is open. A quick caveat — San Diego's clocks move for daylight saving and Shanghai's don't, so the times here are right for only part of the year.