I use below to output data to a excel file using PHP,
Code:
echo "<html xmlns:o=\"urn:schemas-microsoft-com:office:office\" xmlns:x=\"urn:schemas-microsoft-com:office:excel\" xmlns=\"http://www.w3.org/TR/REC-html40\">";
		echo "<head>";
		echo "<meta http-equiv=Content-Type content=\"text/html; charset=us-ascii\"> <meta name=ProgId content=Excel.Sheet><meta
...