size_format()

[KarelWintersky]

/**
 *
 * @param int $size
 * @param int $decimals
 * @param string $decimal_separator
 * @param string $thousands_separator
 * @return string
 */
function size_format(int $size, int $decimals = 0, string $decimal_separator = '.', string $thousands_separator = ','): string {
    $units = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
    $index = min(floor((strlen(strval($size)) - 1) / 3), count($units) - 1);
    $number = number_format($size / pow(1000, $index), $decimals, $decimal_separator, $thousands_separator);
    return sprintf('%s %s', $number, $units[$index]);
}