JAVASCRIPT

moment timezone get offset from iana timezone

import moment from 'moment-timezone'

moment().tz(timezoneName).utcOffset()

moment date without timezone

moment().utcOffset(0, true).format()

moment timezone get timezone offset

moment(date).utcOffset()

moment timezone set default timezone

moment.tz.setDefault("America/New_York");

moment get timezone

var tz = moment.tz.guess();

moment timezone set clock in another timezone

moment.tz(
  new Date().toJSON().split('T')[0] + ' 5:00 PM', 
  'YYYY-MM-DD h:mm A', 
  'America/New_York'
)

momentjs display timezone

moment().utcOffset(0, false).format()

//in format use by your need