Best overlap: 8:00 AM to 3:00 PM in Amsterdam is 11:30 AM to 6:30 PM in Kolkata.
For the smoothest call, aim inside 8:00 AM to 3:00 PM in Amsterdam, i.e. 11:30 AM to 6:30 PM in Kolkata. The overlap is wide at 7 hours, so you can protect mornings for deep work and still find plenty of meeting time. For part of the year the maths changes: Amsterdam observes daylight saving, Kolkata does not, shifting the overlap by an hour.
| Local time | 12am | 1am | 2am | 3am | 4am | 5am | 6am | 7am | 8am | 9am | 10am | 11am | 12pm | 1pm | 2pm | 3pm | 4pm | 5pm | 6pm | 7pm | 8pm | 9pm | 10pm | 11pm |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Amsterdam Europe/Amsterdam | ||||||||||||||||||||||||
Kolkata Asia/Kolkata |
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