javascriptdatedatetimedate-fns

date-fns | How do I format to UTC

Problem

It looks like when I use the format() function, it automatically convert the original UTC time into my timezone (UTC+8). I have been digging through their docs for hours and couldn't seem to find a way to default it to UTC time.

import { parseISO, format } from "date-fns";

const time = "2019-10-25T08:10:00Z";

const parsedTime = parseISO(time);
console.log(parsedTime); // 2019-10-25T08:10:00.000Z

const formattedTime = format(parsedTime, "yyyy-MM-dd kk:mm:ss");
console.log(formattedTime); // 2019-10-25 16:10:00 <-- 8 HOURS OFF!!

I have tried to use the package data-fns-tz and use something like

format(parsedTime, "yyyy-MM-dd kk:mm:ss", {timeZone: "UTC"});

still no luck.

Please help!

Expected Output

2019-10-25 08:10:00

Actual Output

2019-10-25 16:10:00

Solution

  • I would suggest using the built-in Date util:

    const date = new Date("2019-10-25T08:10:00Z");
const isoDate = date.toISOString();

console.log(`${isoDate.substring(0, 10)} ${isoDate.substring(11, 19)}`);

    Outputs:

    2019-10-25 08:10:00

    Not a general solution for any format, but no external libraries required.