You need to send proper html headers that say the message in wrote in html. This following code is a basic example of what i use
//define the receiver of the email
$to = 'youraddress@example.com';
//define the subject of the email
$subject = 'Test HTML email';
//create a boundary string. It must be unique
//so we use the MD5 algorithm to generate a random hash
$random_hash = md5(date('r', time()));
//define the headers we want passed. Note that they are separated with \r\n
$headers = "From: webmaster@example.com\r\nReply-To: webmaster@example.com";
//add boundary string and mime type specification
$headers .= "\r\nContent-Type: multipart/alternative; boundary=\"PHP-alt-".$random_hash."\"";
//define the body of the message.
ob_start(); //Turn on output buffering
?>
--PHP-alt-
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Hello World!!!
This is simple text email message.
--PHP-alt-
Content-Type: text/html; charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Hello World!
This is something with HTML formatting.
--PHP-alt---
//copy current buffer contents into $message variable and delete current output buffer
$message = ob_get_clean();
//send the email
$mail_sent = @mail( $to, $subject, $message, $headers );
//if the message is sent successfully print "Mail sent". Otherwise print "Mail failed"
echo $mail_sent ? "Mail sent" : "Mail failed";
?>
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This is able to send a html message but if the recipient of the email doesnt accept html or html is turned off the plain text version is send. Id advise using this code with $_POST or $_Get commands so you dont need to keep working with the code.