Istanbul to Kolkata (Calcutta): time difference
Kolkata (Calcutta) is 2 h 30 min ahead of Istanbul. Live clocks for both, the working hours they share, and how each one sits against your own time.
🇮🇳 Kolkata (Calcutta), India
10
- India Standard Time
- UTC+5:30
- Golden hour
☀️ 05:32 · 🌙 17:17 · 11 h 46 min
+2 h 30 min
Your time
One day, 2 clocks
Drag along the band to read any hour in every place at once.
Istanbul 14:23 2:23 PM Kolkata (Calcutta) 16:53 4:53 PM You –:–
14:23 2:23 PM
GMT+03:00 · UTC+3
☀️ 07:10 · 🌙 18:33
16:53 4:53 PM
India Standard Time · UTC+5:30
☀️ 05:32 · 🌙 17:17
·
+2 h 30 min
Kolkata (Calcutta) is 2 h 30 min ahead of Istanbul.
When you, Istanbul and Kolkata (Calcutta) are all at the desk
Pick the working hours below – the window every location shares appears once your time zone is known.
Working hours
🇹🇷 Istanbul
0 12 AM 1 1 AM 2 2 AM 3 3 AM 4 4 AM 5 5 AM 6 6 AM 7 7 AM 8 8 AM 9 9 AM 10 10 AM 11 11 AM 12 12 PM 13 1 PM 14 2 PM 15 3 PM 16 4 PM 17 5 PM 18 6 PM 19 7 PM 20 8 PM 21 9 PM 22 10 PM 23 11 PM
🇮🇳 Kolkata (Calcutta)
2:30 2:30 AM 3:30 3:30 AM 4:30 4:30 AM 5:30 5:30 AM 6:30 6:30 AM 7:30 7:30 AM 8:30 8:30 AM 9:30 9:30 AM 10:30 10:30 AM 11:30 11:30 AM 12:30 12:30 PM 13:30 1:30 PM 14:30 2:30 PM 15:30 3:30 PM 16:30 4:30 PM 17:30 5:30 PM 18:30 6:30 PM 19:30 7:30 PM 20:30 8:30 PM 21:30 9:30 PM 22:30 10:30 PM 23:30 11:30 PM 0:30 12:30 AM 1:30 1:30 AM
📍 Your time
- Asleep
- Early
- Working hours
- Evening
- Both working
- Right now
Time zones side by side
| Detail | 🇹🇷 Istanbul | 🇮🇳 Kolkata (Calcutta) |
|---|---|---|
| Local time | 14:23 | 16:53 |
| Local date | Saturday, October 10, 2026 | Saturday, October 10, 2026 |
| Time zone | GMT+03:00 | India Standard Time |
| UTC offset | UTC+3 | UTC+5:30 |
| Offset from Istanbul | — | +2 h 30 min |
| IANA zone | Europe/Istanbul | Asia/Kolkata |
| Daylight saving | Not observed | Not observed |
| Sunrise | 07:10 | 05:32 |
| Sunset | 18:33 | 17:17 |
| Daylight | 11 h 23 min | 11 h 46 min |
| People on this clock | 15,701,602 | 4,486,679 |
Compare Istanbul with another city
More comparisons with Istanbul: the time zones next to it and the far side of the clock.
Big time differences
Istanbul and Kolkata (Calcutta): common questions
How many hours ahead of Istanbul is Kolkata (Calcutta)?
The clocks in Kolkata are 2 hours and 30 minutes ahead of those in Istanbul (UTC+5:30 and UTC+3).
What time is it in Kolkata (Calcutta) when it is 9:00 AM in Istanbul?
When it is 9:00 AM in Istanbul, it is 11:30 AM in Kolkata.
What time is it in Kolkata (Calcutta) when it is 6:00 PM in Istanbul?
When it is 6:00 PM in Istanbul, it is 8:30 PM in Kolkata.
When is a good time to call Kolkata (Calcutta) from Istanbul?
Between 9:00 AM and 3:30 PM in Istanbul – that is 11:30 AM to 6:00 PM in Kolkata – both places are within working hours (9:00 AM–6:00 PM).
When does the date change in Kolkata (Calcutta) compared with Istanbul?
The new day starts in Kolkata earlier: at 9:30 PM in Istanbul it is already midnight there. Until 2:30 AM in Kolkata, Istanbul is still on the previous day.
Does the time gap between Istanbul and Kolkata (Calcutta) change during the year?
No, the clocks change neither in Istanbul nor in Kolkata, so the gap is 2 hours and 30 minutes all year round.
