How to get current time in milliseconds in PHP?

Shortest version of string variant (32-bit compatibile):

$milliseconds = date_create()->format('Uv');

PHP 5.2.2 <

$d = new DateTime();
echo $d->format("Y-m-d H:i:s.u"); // u : Microseconds

PHP 7.0.0 < 7.1

$d = new DateTime();
echo $d->format("Y-m-d H:i:s.v"); // v : Milliseconds 

If you want to see real microseconds, you will need to change the precision setting in php.ini to 16.

After that, microsecond(true) gave me the output of 1631882476.298437.

So I thought that I need to divide the remainder (298437) with 1000, but in fact, the remainder is 0.298437 of a second. So I need to multiply that by 1000 to get the correct result.

    function get_milliseconds()
    {
        $timestamp = microtime(true);
        return (int)(($timestamp - (int)$timestamp) * 1000);
    }

I personaly use this:

public static function formatMicrotimestamp(DateTimeInterface $dateTime): int
{
    return (int) substr($dateTime->format('Uu'), 0, 13);
}

This is my implementation, should work on 32bit as well.

function mstime(){
    $mstime = explode(' ',microtime());
    return $mstime[1].''.(int)($mstime[0]*1000);
}