Mathematical differences?!

Hello all, I ported a algorithm from JavaScript to PHP and noticed that PHP outputs a different result than JS. For example: ==================== t = 0.6255264658909423 f = 20.5 ln = -6.983333333333333 d2r = 0.017453292519943295 $ra = (((6.6460656 + 2400.0513 * $t + 2.58e-5 * $t * $t + $f) * 15 - $ln) % 360) * $d2r; PHP outputs 4.4156830075456535 JS outputs 4.42304792511156 ==================== I found out that ((...) % 360) returns in PHP 253.0000... whereas JS and a Calculator return 253.6085.... I also tried to use the bc...-functions but the result was the same. This formular is only a part of a bigger calculation and I also noticed further differences because when I manually set $ra to 4.4230... (the JS result) then I still get a different end-result than in JS but it is 100% EXACTLY the same algorithm, I checked it many times. How could that be?! 1:1 the same code but different outputs? Is this a PHP-bug? :-? Kindly regards, Mario