Worldtimebuddy is great but if you're looking for something even better, on Mac you cannot beat 'The Clock' app. Exact same functionality as Worldtimebuddy but

Worldtimebuddy is great but if you're looking for something even better, on Mac you cannot beat 'The Clock' app. Exact same functionality as Worldtimebuddy but goes farther and allows renaming those clocks. If Dan is on EST and Jules is on NRT, rename the EST clock to Dan and the NRT clock to Jules and slide back and forth to easily do the timezone math. If you work for a cloud company and need to schedule cross AZ work this little app will save your life. What is local time in IAD when SYD is doing 10PM maintenance local time? What about NRT? :-)