How long is the flight to Osaka?
The below times are for non stop flight segments to Kansai International Airport (KIX). From Seattle Tacoma International Airport (SEA), the flight time is roughly 10 hours and 50 minutes. From San Francisco International Airport (SFO), the flight time is roughly 11 hours and 14 minutes. From Honolulu International Airport (HNL), the flight time is roughly 8 hours and 49 minutes.
Please keep in mind that the above are time in the air; most travel sites will quote a ramp to ramp time which is about a 1/2 hour greater than the air time.