Mumbai is 12.5-13.5 hours ahead of San Francisco. Mumbai uses Indian Standard Time (IST, UTC+5:30) while San Francisco uses Pacific Time (PST/PDT, UTC-8/-7). During standard time, Mumbai is 13.5 hours ahead; during daylight saving time, Mumbai is 12.5 hours ahead.
India does not observe daylight saving time, while the US does, so the difference varies seasonally.
Best calling time: 9:00 PM - 11:30 PM Mumbai time. This corresponds to 8:30 AM - 11:00 AM in San Francisco, covering morning business hours.
Mumbai and San Francisco are major tech hubs with extensive business ties. Many tech companies have offices in both cities, creating a strong India-Silicon Valley corridor. Direct flights take about 17 hours.