Php get timezone

Is there a way, using only php to get the clients timezone, can´t use any client side scripting since my code runs in the home page.

No. PHP is SERVER SIDE. I’m sure I don’t need to explain that.

Yes I do understand that, I was just hoping that through the server there was a way to do it.

You could do this with JavaScript though and send the data back to PHP to store in the user’s session.

why can you not use it on client dide ? I don’t understand.

Because the time is calculated in php and then sent back to the browser, although I could calculate the timezone difference once it gets to the browser

of course. sorry for the stupid question.