Time in Busan vs Kolkata
Busan keeps KST (UTC+9) and Kolkata keeps IST (UTC+5:30) today. Kolkata is 3½ hours behind Busan; the rows below read both clocks live.
The working day, side by side
Hours shaded in both rows are inside working hours in both cities: 09:00–15:00 in Kolkata (12:00–18:00 your time).
| City | 00:00 in Busan | 01:00 in Busan | 02:00 in Busan | 03:00 in Busan | 04:00 in Busan | 05:00 in Busan | 06:00 in Busan | 07:00 in Busan | 08:00 in Busan | 09:00 in Busan | 10:00 in Busan | 11:00 in Busan | 12:00 in Busan | 13:00 in Busan | 14:00 in Busan | 15:00 in Busan | 16:00 in Busan | 17:00 in Busan | 18:00 in Busan | 19:00 in Busan | 20:00 in Busan | 21:00 in Busan | 22:00 in Busan | 23:00 in Busan |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Busan—— | 00 | 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 |
| Kolkata—— | 00 | 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 |
- Working hours
- Shoulder
- Night
- Overlap
Do more with Busan and Kolkata
Best hours to call
12:00 in Busan
Inside working hours on both sides
09:00 in Kolkata
13:00 in Busan
Inside working hours on both sides
10:00 in Kolkata
14:00 in Busan
Inside working hours on both sides
11:00 in Kolkata
15:00 in Busan
Inside working hours on both sides
12:00 in Kolkata
Where daylight saving pulls them apart
Neither Busan nor Kolkata changes its clocks, so the gap above holds all year.
Also useful
Common questions
How many hours ahead is Kolkata of Busan?
Kolkata is 3½ hours behind Busan right now. The gap is not fixed: it moves whenever either side changes its clocks.
What is the best time to call between Busan and Kolkata?
Any hour in 12:00–18:00 Busan time is inside working hours in both cities.
Do Busan and Kolkata change clocks on the same date?
Neither city changes its clocks, so the gap between them never moves.