Check Whether user belongs to SharePoint Group using REST api

How to Check Whether user belongs to SharePoint Group using REST api

Code - 

$(document).ready(function(){
    isOwnerGroupMember();
 });

function isOwnerGroupMember() {
    $.ajax({
        url: _spPageContextInfo.webAbsoluteUrl + "/_api/web/sitegroups/getByName('Test Owners')/Users?$filter=Id eq " + _spPageContextInfo.userId,
        method: "GET",
        async: false,
        headers: {
            "Accept": "application/json; odata=verbose"
        },
        success: function(data) {
            if (data.d.results.length == 0) {
                console.log("User not in group : Test Owners");
                         
            }
            else {
                console.log("User in group : Test Owners"); 
                           
            }
        },
        error: function(err) {
            console.log("Error while checking user in Owner's group");         
        }
    });
}

By using above code you can check whether logged in user is member of the SharePoint Group or not. You can apply your own logic based on your business requirement.