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phpdatetimeutc

IST to UTC timestamp in php

I have a date time like 30-10-2018 06:00:00 pm, Now I want to convert it into UTC timestamp, so I am trying to convert this to strtotime and multiplying it by 1000. But it leading to 6hrs difference in the resulted date

$min_date = "30-10-2018 06:00:00 pm";
$max_date= "30-10-2018 07:00:00 pm";

echo $minDate= strtotime($min_date) * 1000; 
echo "<br>";
echo $maxDate= strtotime($max_date) * 1000;
Solution

  • What you want to use is a built-in PHP function known as "gmdate."

    Let's use your first timestamp, $min_date, in our example of using gmdate to convert the datetime string to a UTC timestamp:

    $min_date = "30-10-2018 06:00:00 pm";

//Use 'gmdate', which accepts a formatting string and time() values as arguments.
$utc_min_date = gmdate("d-m-Y H:i:s", strtotime($min_date));

echo "<p>Before: ".$min_date."</p>"; 
//Produces: "Before: 30-10-2018 06:00:00 pm"

echo "<p>UTC: ".$utc_min_date."</p>"; 
//Produces: "UTC: 30-10-2018 23:00:00"

    If you're wanting a purely numerical representation, akin to a time() stamp, you can simply convert the resulting UTC timestamp.

    $numerical_utc_min_date = strtotime($utc_min_date);

echo "<p>Numerical UTC timestamp: " . $numerical_utc_min_date . "</p>";
//Produces: "Numerical UTC timestamp: 1540958400"