PHP filesize bytes convert KB MB GB TB

Convert File Size to Human Readable Format in PHP. Converting bytes to human readable values (KB, MB, GB, TB, PB) PHP function

1 Byte = 8 Bits
1 Kilobyte = 1024 Bytes
1 Megabyte = 1048576 Bytes
1 Gigabyte = 1073741824 Bytes
1 Terabyte = 1099511627776 bytes
function
<?php
function formatBytes($bytes) {
	if ($bytes > 0) {
		$i = floor(log($bytes) / log(1024));
		$sizes = array('B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB');
		return sprintf('%.02F', round($bytes / pow(1024, $i),1)) * 1 . ' ' . @$sizes[$i];
	} else {
		return 0;
	}
}
?>
usage
<?php
echo formatBytes('1000'); // 1000B

echo formatBytes('1073741824'); //1GB
?>
<?php
$file_size = filesize('myfile.zip'); // Get file size
echo '<div title="'.$file_size.' bytes">'.formatBytes($file_size).'</div>';

 //output 
 //<div title="1073741824 bytes">1 GB</div>
?>