IST to BST
Converting a fixed time. Asia/Kolkata → Europe/London
3:30 pm in IST is
11:00 am in BST.
15:30 → 11:00 on a 24-hour clock ·
IST → BST
IST now
11:33pm
IST · UTC+5:30
Asia/Kolkata
Clocks here do not change — this zone stays on the same offset all year.
BST now
7:03pm
BST · UTC+1
Europe/London
Clocks go back 1 hour on Sunday, 25th October 2026, at 1:59 am local time (1:00 am after the change).
Convert a specific time minutes work, not just whole hours
Hour by hour
| IST | BST | 24h | Good to call? |
|---|---|---|---|
| 12am | 7pm Wed | 00:00 → 19:30 | asleep in IST |
| 1am | 8pm Wed | 01:00 → 20:30 | asleep in IST |
| 2am | 9pm Wed | 02:00 → 21:30 | asleep in IST |
| 3am | 10pm Wed | 03:00 → 22:30 | asleep in BST |
| 4am | 11pm Wed | 04:00 → 23:30 | asleep in BST |
| 5am | 12am | 05:00 → 00:30 | asleep in BST |
| 6am | 1am | 06:00 → 01:30 | asleep in BST |
| 7am | 2am | 07:00 → 02:30 | asleep in BST |
| 8am | 3am | 08:00 → 03:30 | asleep in BST |
| 9am | 4am | 09:00 → 04:30 | asleep in BST |
| 10am | 5am | 10:00 → 05:30 | asleep in BST |
| 11am | 6am | 11:00 → 06:30 | asleep in BST |
| 12pm | 7am | 12:00 → 07:30 | awake, not at work |
| 1pm | 8am | 13:00 → 08:30 | awake, not at work |
| 2pm | 9am | 14:00 → 09:30 | both at work |
| 3pm | 10am | 15:00 → 10:30 | both at work |
| 4pm | 11am | 16:00 → 11:30 | both at work |
| 5pm | 12pm | 17:00 → 12:30 | awake, not at work |
| 6pm | 1pm | 18:00 → 13:30 | awake, not at work |
| 7pm | 2pm | 19:00 → 14:30 | awake, not at work |
| 8pm | 3pm | 20:00 → 15:30 | awake, not at work |
| 9pm | 4pm | 21:00 → 16:30 | awake, not at work |
| 10pm | 5pm | 22:00 → 17:30 | asleep in IST |
| 11pm now | 6pm | 23:00 → 18:30 | asleep in IST |
Call times
Both places are at work between 2pm and 17:00 in Kolkata — 9am to 11am at the other end.
12am
7pm
7pm
1am
8pm
8pm
2am
9pm
9pm
3am
10pm
10pm
4am
11pm
11pm
5am
12am
12am
6am
1am
1am
7am
2am
2am
8am
3am
3am
9am
4am
4am
10am
5am
5am
11am
6am
6am
12pm
7am
7am
1pm
8am
8am
2pm
9am
9am
3pm
10am
10am
4pm
11am
11am
5pm
12pm
12pm
6pm
1pm
1pm
7pm
2pm
2pm
8pm
3pm
3pm
9pm
4pm
4pm
10pm
5pm
5pm
11pm
6pm
6pm
both at work
work hours here
awake
asleep
Questions people ask
What time is it in BST when it is 3:30 pm in IST?
11:00 am in BST the same day.
How many hours ahead is BST of IST?
BST is 4 hours 30 minutes behind IST. That gap is not fixed: it changes when either place starts or ends daylight saving. The table on this page is recalculated for today, so it is already correct for the current season.
What is the best time to call between IST and BST?
Both places are at work between 2pm and 17:00 in Kolkata — 9am to 11am at the other end.