用户端分别时间

Hello I am trying to make a web application where users can ask question about their related problems:

The function in which I am stuck is that how can the end users get to know about the timing timing of thew question in their respective time zones?

For example I sitting in Kolkata/Asia time zone posted this question right now and at the same time a person from Western Hemisphere sees the question at the same time saying that this question was posted just 1 min ago.

or suppose a person sees it after 26 hours so it will show that it was posted 1 day 2 hours ago or it will show a respective date in respect to its local time zone for example , posted on 12th Aug, 2014 in Asia/Kolkata hence it should the proper date in respected usere's local time zone

Just for Note: I am making this web project using php, mysqli, js, ajax

Use either standard time like UTC, or server time. It doesn't matter where I am and what time it is now here, nor where you are and what time it is there: it has been several minutes between the time the server accepted your question, and the time it received my answer.