src/Debug/Utilities.php
public static function getBytes($size)
    {
        if (\is_string($size) && \preg_match('/^([\d,.]+)\s?([kmgtp])b?$/i', $size, $matches)) {
            $size = \str_replace(',', '', $matches[1]);
            switch (\strtolower($matches[2])) {
                case 'p':
                    $size *= 1024;
                    // no break
                case 't':
                    $size *= 1024;
                    // no break
                case 'g':
                    $size *= 1024;
                    // no break
                case 'm':
                    $size *= 1024;
                    // no break
                case 'k':
                    $size *= 1024;
            }
        }
        $units = array('B','kB','MB','GB','TB','PB');
        $pow = \pow(1024, ($i=\floor(\log($size, 1024))));
        $size = $pow == 0
            ? '0 B'
            : \round($size/$pow, 2).' '.$units[$i];
        return $size;
    }
public static function getBytes($size)
    {
        if (\is_string($size) && \preg_match('/^([\d,.]+)\s?([kmgtp])b?$/i', $size, $matches)) {
            $size = \str_replace(',', '', $matches[1]);
            switch (\strtolower($matches[2])) {
                case 'p':
                    $size *= 1024;
                    // no break
                case 't':
                    $size *= 1024;
                    // no break
                case 'g':
                    $size *= 1024;
                    // no break
                case 'm':
                    $size *= 1024;
                    // no break
                case 'k':
                    $size *= 1024;
            }
        }
        $units = array('B','kB','MB','GB','TB','PB');
        $pow = \pow(1024, ($i=\floor(\log($size, 1024))));
        $size = $pow == 0
            ? '0 B'
            : \round($size/$pow, 2).' '.$units[$i];
        return $size;
    }
Convert size int into "1.23 kB"

@param integer|string $size bytes or similar to "1.23M"

@return string