Flight Changi Airport departs from Singapore Changi Airport at 19:50 and arrives at San Francisco International Airport at 20:15.
The flighttime is about 15h 25m. The distance travelled ("as the bird flies"): 15083 Km. So the average speed is roughly 978 Km.
There is an 15 hour time difference between Singapore and San Francisco
The best day to arrive at Singapore is Tuesday and it would be best to avoid Thursday, as prices are on average 197.32% higher than on Tuesday. (Average prices, based on 125523 datapoints.)
We have a lot more statistics for flights SQ 34 and between Singapore and San Francisco.