CDN hosted jQuery based Autocomplete script with Millions of Suggestions. Details: https://knowledgebasehub.com

google-autocomplete.js

var KnowledgebaseHub;
$(document).ready(function () {
    $("#search").autocomplete({
        source: function(request, response) {
            $.getJSON("https://suggestqueries.google.com/complete/search?callback=?",
                {
                  "hl":"en", // "en" is english. see documentation for more languages
                  "ds":"", // Force youtube suggestions, use "yt"			  
                  "jsonp":"KnowledgebaseHub", // jsonp callback function name
                  "q":request.term, // search term
                  "client":"youtube" // force jsonp response
                }
            );
            KnowledgebaseHub = function (data) {
                var suggestions = [];
                $.each(data[1], function(key, val) {
                    suggestions.push({"value":val[0]});
                });
                suggestions.length = 5; // show upto 10 suggestions
                response(suggestions);
            };
        },
    });
});