JST to IST

The difference month by month, the same on every date the pinned table covers, and what that means for a call between Tokyo and Mumbai.

How far apart are JST and IST?

IST is 3 hours, 30 minutes behind JST on every date the pinned table covers.

When it is 9:00 AM in Tokyo, it is 5:30 AM in Mumbai.

Right now

The current reading appears once this page finishes loading.

How does the difference change month by month?

The difference is the same in every month of 2026, which is unusual for a zone pair and worth checking rather than assuming. Here it is, month by month.

Show the month-by-month table

Difference between JST and IST by month, 2026
Month	Difference	Changes on
January	−3:30	No change
February	−3:30	No change
March	−3:30	No change
April	−3:30	No change
May	−3:30	No change
June	−3:30	No change
July	−3:30	No change
August	−3:30	No change
September	−3:30	No change
October	−3:30	No change
November	−3:30	No change
December	−3:30	No change

Dates here are calendar dates in JST time. Where a clock change happens overnight, the calendar in the other zone can already have turned over.

When does the usual difference not hold?

It always holds. Neither zone moves its clocks, so the difference is the same on every date the pinned table covers.

Every offset on this page comes from IANA tzdata 2026c, released July 8, 2026. The pinned table covers 2024–2032. How these times are derived