How to handle time input for different time zones?

Question

My application allows an admin to enter a time window when they would like certain features to be available to a user. I tested it in a dev environment, and everything works great.

The problem is that most of my user base is located in the western United States, in the Mountain States, an area of the US where Daylight Savings time is not observed, and my production servers are located on the east coast, and I calculate the time based on the server's time.

So when entering the time, the admin might enter 13:00 - 16:00 as the time window, but they meant for MST, and the server will calculate the time window as it's OWN 13:00 - 16:00, so the user base will experience the window as 10:00 - 13:00.

My solutions are:

1. Inform the user that the time window will be in EST
2. Let them enter the time in MST (as my customers are mainly located in MST areas) and calculate the difference in my code, handling the daylight savings time as well.

I can see the merits in both, but what is the best user experience?

Answer 1

The best user experience is the one where the user has to think about this stuff as little as possible.

Offer the user the ability to specify whichever timezone they deem most appropriate and handle the conversion and calculation in the code.

Because your users are mainly in MST, make that the default.

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