EDT vs JST time zone comparison

How EDT and JST compare

Eastern Daylight Time (EDT) sits at UTC-04:00 today, while Japan Standard Time (JST) is at UTC+09:00. The current gap is 13 hours, with EDT behind JST. In practical terms, if your morning starts at 9 AM in New York, your counterpart in Tokyo is seeing 22:00 on their own watch at that exact moment.

EDT is the working clock for New York, New York City and Washington DC. EDT is the summer version of EST. Same IANA zone, automatic switch on the second Sunday of March and first Sunday of November. JST covers Tokyo, Osaka and Yokohama. If your team is split between these two regions, the table above is the quickest way to spot the daily overlap window without doing the offset arithmetic in your head.

Daylight saving matters here. Eastern Daylight Time shifts forward an hour on the second Sunday of March (US) or the last Sunday of March (Europe) and back on the first Sunday of November or last Sunday of October. Japan Standard Time stays on a fixed offset year-round. The IANA tzdata baked into this page handles every transition automatically, so the table reflects the correct wall-clock times for today's date. For dates further out, use the converter linked above and pick the target date explicitly.

Common scheduling traps are easy to avoid here. Pick a wall-clock time on one side, read the matching wall-clock on the other from the table, and write both into the calendar invite, never just the difference. If the meeting falls in the week of a DST changeover and one of these zones shifts, the absolute clock will drift by an hour from what the recipient expects. The table is computed for today's date, so for a future meeting open the converter linked above and pick the exact date.

One last note for asynchronous teams: business-hour overlap is the wrong metric for handoff workflows. If you operate on a follow-the-sun model, you actually want zero overlap, with one team logging off as the other starts. EDT and JST differ by 13 hours, which gives you partial coverage. Add a zone in between if you want full 24-hour rotation.