Time in Tehran vs Kolkata
Tehran keeps UTC+3:30 (UTC+3:30) and Kolkata keeps IST (UTC+5:30) today. Kolkata is 2 hours ahead of Tehran; 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: 11:00–18:00 in Kolkata (09:00–16:00 your time).
| City | 00:00 in Tehran | 01:00 in Tehran | 02:00 in Tehran | 03:00 in Tehran | 04:00 in Tehran | 05:00 in Tehran | 06:00 in Tehran | 07:00 in Tehran | 08:00 in Tehran | 09:00 in Tehran | 10:00 in Tehran | 11:00 in Tehran | 12:00 in Tehran | 13:00 in Tehran | 14:00 in Tehran | 15:00 in Tehran | 16:00 in Tehran | 17:00 in Tehran | 18:00 in Tehran | 19:00 in Tehran | 20:00 in Tehran | 21:00 in Tehran | 22:00 in Tehran | 23:00 in Tehran |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tehran—— | 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 Tehran and Kolkata
Best hours to call
09:00 in Tehran
Inside working hours on both sides
11:00 in Kolkata
10:00 in Tehran
Inside working hours on both sides
12:00 in Kolkata
11:00 in Tehran
Inside working hours on both sides
13:00 in Kolkata
12:00 in Tehran
Inside working hours on both sides
14:00 in Kolkata
Where daylight saving pulls them apart
Neither Tehran nor Kolkata changes its clocks, so the gap above holds all year.
Also useful
Common questions
How many hours ahead is Kolkata of Tehran?
Kolkata is 2 hours ahead of Tehran right now. The gap is not fixed: it moves whenever either side changes its clocks.
What is the best time to call between Tehran and Kolkata?
Any hour in 09:00–16:00 Tehran time is inside working hours in both cities.
Do Tehran and Kolkata change clocks on the same date?
Neither city changes its clocks, so the gap between them never moves.