ISO-8601 UTC datetimes in web-applications

2 minute read

The best way to handle dates in web-apps (especially a backend side) is using ISO-8601 standart (DB dates, input params, responses).

An example of an ISO-8601 UTC datetime: ‘2019-03-02T13:27:40Z’.


  • npm install moment –save or npm install moment-timezone –save:
const moment = require('moment-timezone');
  • get a Moment (UTC mode) by a current system time:
  • print a current system time (my system time is GMT+5):
// > '2019-03-02T18:27:40+05:00'
  • print a current system UTC time (my system time is GMT+5)
// > '2019-03-02T13:27:40Z'
  • get a Moment (UTC mode) by a UTC date (string)
const utcDateString = '2019-03-02T13:27:40Z';
  • get a JS Date by a UTC date (string)
  • check is a valid ISO 8601 date (string)
const isValidDate = moment(utcDateString, moment.ISO_8601).isValid();
  • convert a UTC date (string) to a Moment with changed timeozne
    1. get a JS Date by a UTC date (string)
    2. change the timezone to ‘America/Los_Angeles’
  • convert a timezone date (string) to a Moment (with a timezone offset)
    1. get a Moment by a date (string) and a timezone
    2. get a Moment (UTC mode)
const losAngelesDate = 'March 2nd 2019, 5:27:40 am';, 'MMMM Do YYYY, h:mm:ss a', 'America/Los_Angeles').utc();
// > 2019-03-02T13:27:40Z