var options = { attributes: { rel: 'nofollow', title: 'click to open', }, className: 'internal-link', format: { url: function (value) { return value } }, ignoreTags: ['a'], validate: { url: function (value) { return /^(http|ftp)s?:\/\//.test(value); } } }; var str = 'NAM Website Index'; document.write(linkifyHtml(str, options));