JST to GMT Converter

It takes three quick steps:

1. Click the JST field on the left and pick the time you want to convert.
2. The matching GMT time updates on the right automatically — there’s no button to press.
3. Need a different day? Click the date field and the result follows, rolling over if it crosses midnight.

GMT is 9 hours behind JST. In everyday terms, once you know the time on one side you just subtract 9 hours to get the other — so a call between Tokyo and London (winter) is always 9 hours apart.

Right now the time in Greenwich Mean Time (GMT) is Monday, June 29, 2026 · 5:54:04 PM. It ticks every second, so you’re always looking at the live GMT clock.

And in Japan Standard Time (JST), it’s currently Tuesday, June 30, 2026 · 2:54:04 AM. Compare the two and the 9 hours gap is easy to see.

For example, a 9:00 AM JST meeting takes place at 12:00 AM GMT. The trick is to aim for a slot that lands inside normal working hours on both sides. Once you’ve found a time, hit Share on the converter to copy a link with the time built in — easy to send to a colleague. Juggling three or more zones? The meeting planner highlights the hours that overlap for everyone.

The labels JST and GMT are fixed offsets, so the result on this page is always exact. Neither side changes its clocks for daylight saving, so the difference you see here is the same in summer and winter.

Every conversion here is calculated from the IANA time zone database — the same source your phone, computer, and browser rely on. Plenty of tools hard-code a single offset, which quietly goes wrong whenever a region changes its rules or flips for daylight saving. We follow the real rules instead, so JST to GMT stays accurate for today and for any past or future date you type in.