<?php
function parsebytesize($size, $digits = 1, $dir = false) {
	$kb = 1024; $mb = 1024 * $kb; $gb= 1024 * $mb; $tb = 1024 * $gb; $pt = 1024 * $tb;
	if ($size == 0) { return "0Байтов"; }
	elseif ($size < $kb) { return $size."Байтов"; }
	elseif ($size < $mb) { return round($size / $kb,$digits)."КБ"; }
	elseif ($size < $gb) { return round($size / $mb,$digits)."МБ"; }
	elseif ($size < $tb) { return round($size / $gb,$digits)."ГБ"; }
	elseif ($size < $pt) { return round($size / $tb,$digits)."ТБ"; }
	else { return round($size / $pt, $digits)."ПБ"; }
}

$dfs = @disk_free_space(".");
echo parsebytesize($dfs,5);
?>