Kolkata Time to JST Converter
JST is 3 hours 30 minutes ahead of IST. 9:00 AM IST = 12:30 PM JST.
JST is 3 hours 30 minutes ahead of IST. To convert Kolkata Time to JST, add 3 hours 30 minutes to the Kolkata Time time: 9:00 AM IST = 12:30 PM JST.
Kolkata Time (Kolkata time) is used in Kolkata, India. JST (Japan Time) is used in Japan.
Kolkata Time to JST time conversion table
Kolkata Time to JST on 7 Nov 2026. Today's date. Highlighted rows are 9 AM–5 PM in both places.
| Kolkata Time | JST | Day |
|---|---|---|
| 12:00 AM IST | 3:30 AM JST | night |
| 1:00 AM IST | 4:30 AM JST | night |
| 2:00 AM IST | 5:30 AM JST | night |
| 3:00 AM IST | 6:30 AM JST | — |
| 4:00 AM IST | 7:30 AM JST | — |
| 5:00 AM IST | 8:30 AM JST | — |
| 6:00 AM IST | 9:30 AM JST | — |
| 7:00 AM IST | 10:30 AM JST | — |
| 8:00 AM IST | 11:30 AM JST | — |
| 9:00 AM IST | 12:30 PM JST | work hours |
| 10:00 AM IST | 1:30 PM JST | work hours |
| 11:00 AM IST | 2:30 PM JST | work hours |
| 12:00 PM IST | 3:30 PM JST | work hours |
| 1:00 PM IST | 4:30 PM JST | work hours |
| 2:00 PM IST | 5:30 PM JST | — |
| 3:00 PM IST | 6:30 PM JST | — |
| 4:00 PM IST | 7:30 PM JST | — |
| 5:00 PM IST | 8:30 PM JST | — |
| 6:00 PM IST | 9:30 PM JST | — |
| 7:00 PM IST | 10:30 PM JST | night |
| 8:00 PM IST | 11:30 PM JST | night |
| 9:00 PM IST | 12:30 AM JST | next day |
| 10:00 PM IST | 1:30 AM JST | next day |
| 11:00 PM IST | 2:30 AM JST | next day |
- Work rows — 9 AM–5 PM in both places
- Night in the destination (10 PM–6 AM)
How to convert Kolkata Time to JST
Add 3 hours 30 minutes to the Kolkata Time time to get JST.
Example: 9:00 AM IST = 12:30 PM JST.
Across midnight: 10:00 PM IST = 1:30 AM JST (next day). The date changes, so always check the day as well as the hour.
Time difference between Kolkata Time and JST
The time difference between Kolkata Time and JST is 3 hours 30 minutes all year – JST is ahead of IST.
Kolkata Time and JST during daylight saving time
- Kolkata Time does not observe daylight saving time; it stays on UTC+5:30 all year.
- JST does not observe daylight saving time; it stays on UTC+9 all year.
Best time for a meeting between Kolkata Time and JST
Kolkata Time and JST share 4 hours 30 minutes of the 9 AM–5 PM working day. Any time between 9:00 AM and 1:30 PM IST lands between 12:30 PM and 5:00 PM JST, inside working hours for both.
Kolkata Time to JST FAQ
What is the time difference between Kolkata Time and JST?
JST is 3 hours 30 minutes ahead of IST all year. 9:00 AM IST = 12:30 PM JST.
What is 9 AM Kolkata Time in JST?
9:00 AM IST is 12:30 PM JST.
What is 12 PM (noon) Kolkata Time in JST?
12:00 PM IST is 3:30 PM JST.
Is JST ahead of or behind Kolkata Time?
JST is 3 hours 30 minutes ahead of IST, so it is later in JST than in Kolkata Time.
Does Kolkata Time change for daylight saving time?
No. Kolkata Time stays on the same offset all year, so conversions never shift for daylight saving time.
Does JST change for daylight saving time?
No. JST stays on the same offset all year, so conversions never shift for daylight saving time.
What is the best time for a meeting between Kolkata Time and JST?
Kolkata Time and JST share 4 hours 30 minutes of the 9 AM–5 PM working day. Any time between 9:00 AM and 1:30 PM IST lands between 12:30 PM and 5:00 PM JST, inside working hours for both.
Related conversions
Convert JST to Kolkata Time
Convert Kolkata Time to other time zones
Convert other time zones to JST
Learn more
Updated 7 November 2026. Time zone data: IANA tz database.