JST to UTC Time Converter
Coordinated Universal Time (UTC) is currently 9 hours behind Japan Standard Time (JST). JST is UTC+9 and UTC is UTC+0. The table below converts every hour of the day between the two, and the call planner shows where working hours line up.
Best Time for a Call
There is no overlap between 9:00 AM and 5:00 PM office hours in these two zones. Stretching to early mornings and evenings, the workable window runs from 4:00 PM to 9:00 PM in JST, which is 7:00 AM to 12:00 PM in UTC. One side ends up outside normal hours, so alternating who takes the awkward slot is a fair way to handle recurring calls.
Comparing more than two places? The Overlap Zones tool shows working hours for several cities on one grid.
Hour by Hour: JST to UTC
Rows marked office hours fall between 9:00 AM and 5:00 PM in both places. For a specific date, use the interactive converter.
Does the Difference Change During the Year?
JST and UTC are fixed offsets, so the difference between them never changes.
JST is UTC+9. Japan has no daylight saving, so this offset never changes.
UTC is the global time standard. It has no daylight saving and never shifts.
Frequently Asked Questions
How many hours behind is UTC compared to JST?
UTC is currently 9 hours behind JST. JST and UTC are fixed offsets, so the difference between them never changes.
What time is 9:00 AM in JST in UTC?
9:00 AM in JST is 12:00 AM in UTC.
What is the best time for a call between JST and UTC?
There is no overlap between 9:00 AM and 5:00 PM office hours in these two zones. Stretching to early mornings and evenings, the workable window runs from 4:00 PM to 9:00 PM in JST, which is 7:00 AM to 12:00 PM in UTC. One side ends up outside normal hours, so alternating who takes the awkward slot is a fair way to handle recurring calls.