Mailto Encoder test SPAM Evasion Spammers sift through webpages looking for e-mail addresses. The JavaScript FORM above will encode your e-mail address for you. The mailto URL contains only the e-mail address according to the official spec.
Some browsers support additional fields after the address.
This was supported by the original Mosaic and adopted by Netscape. However, Microsoft didn't support it until MSIE v5. Neat social engineering hack.