Guam is always 1 hour ahead of Tokyo. When it's 9:00 AM in Tokyo, it's 10:00 AM in Guam. Neither location observes DST, so the 1-hour difference is constant year-round.
Tokyo uses JST (Japan Standard Time, UTC+9) while Guam uses ChST (Chamorro Standard Time, UTC+10).
Nearly identical business hours! 9:00 AM - 6:00 PM Tokyo corresponds to 10:00 AM - 7:00 PM Guam. Scheduling is straightforward with just 1-hour offset.
Guam is one of the most popular vacation destinations for Japanese tourists, just a 3.5-hour flight from Tokyo. The island hosts many Japanese businesses and resorts.