UTC date not changing in IST date format in PHP

Question

As based on REST API page documentation the date is in UTC format as yyyy-MM-dd'T'HH:mm:ss (Eg: 2017-01-02T08:12:53) When I hit the API, I am getting the date as 1619693307000 . Converted this date using strtotime() in PHP. What is the correct way to convert this date in dmY h:i:s IST in PHP.

I used this code to do the same.

<?php echo date("Y-m-d h:i:s", '1619693307000') ?> //OUTPUT: 53296-01-14 01:00:00 

The above output is absolutely wrong. Confusion is to correctly convert UTC to IST zone and what should i do to see the correct output as the date in PHP. I read all threads on this StackOverflow and Google. but all not helpfull.

Please help...

Answer 1

Your timestamp has too many digits, so it's likely in milliseconds. This seems to be a common javascript thing. So divide by 1000, and I highly recommend using the DateTime objects/interfaces rather than the old-style strtotime() / date() /etc functions.

$millis = 1619693307000;
$seconds = $millis / 1000;

$t = new DateTime('', new DateTimezone('Asia/Kolkata'));
$t->setTimestamp($seconds);

var_dump(
    $t->format("Y-m-d h:i:s T")
);

Output:

string(23) "2021-04-29 04:18:27 IST"

Also "UTC" is not a format, it's a timezone. 2017-01-02T08:12:53 is an ISO8601-format. It also has a handy format shortcut:

var_dump(
    $t->format("c")
);

Output:

string(25) "2021-04-29T16:18:27+05:30"

Edit: Different timezone and format:

$t = new DateTime('', new DateTimezone('UTC'));
$t->setTimestamp($seconds);

var_dump(
    $t->format("Y-m-d\Th:i:s")
);

Output:

string(19) "2021-04-29T10:48:27"