$(document).ready(function(){

                $.ajax({
                    url: _spPageContextInfo.siteAbsoluteUrl + "/_api/web/webs?$expand=Webs",
                    method: "GET",
                    headers: {
                    "Accept": "application/json; odata=verbose"
                    },
                    success: function(data) {

                        for(i=0;i<data.d.results.length;i++){
                                console.log(data.d.results[i].Title;
                            }

                    },
                    error: function(rootsite) {console.log("error   ");},
                    async: false
                    });

});