Http

// Custom
function encodeQueryData(data) {
   const ret = [];
   for (let d in data)
     ret.push(encodeURIComponent(d) + '=' + encodeURIComponent(data[d]));
   return ret.join('&');
}

let my_query = {
    name: 'KJ',
    age: 18
};
let searchParams = encodeQueryData(my_query);

// Browser
let my_query = {
    name: 'KJ',
    age: 18
};

const searchParams = new URLSearchParams(data);

// Node.js
const querystring = require('querystring');

let my_query = {
    name: 'KJ',
    age: 18
};

const searchParams = querystring.stringify(my_query);