date-fns-tz

import { formatInTimeZone, toZonedTime } from 'date-fns-tz'; import { parseISO, format } from 'date-fns'; const dateString = '2024-04-21T18:30:00Z'; // UTC date string const timeZone = 'America/Los_Angeles'; // Parse the ISO string to a Date object (which will be in UTC internally) const utcDate = parseISO(dateString); // Format the UTC date directly into the target timezone const formattedTimeInLA = formatInTimeZone(utcDate, timeZone, 'yyyy-MM-dd HH:mm:ss zzz'); // Convert the UTC date to a Zoned Date object (representing local time in LA) const zonedDateInLA = toZonedTime(utcDate, timeZone); // Format the zoned date using date-fns's format (since it's now a 'local' date in LA) const formattedZonedDate = format(zonedDateInLA, 'yyyy-MM-dd HH:mm:ss'); console.log(`Original UTC: ${dateString}`); console.log(`Formatted in ${timeZone} (with timezone token): ${formattedTimeInLA}`); console.log(`Zoned Date in ${timeZone}: ${zonedDateInLA.toISOString()}`); // Shows as if local time, but internally still UTC console.log(`Formatted Zoned Date in ${timeZone}: ${formattedZonedDate}`);