// Assuming in your HTML code you have the following element
// <pre id="json"></pre>
// Include the code below in your JS file
const data = {
"data": {
"x": "1",
"y": "1",
"url": "http://url.com"
},
"event": "start",
"show": 1,
"id": 50
}
document.getElementById("json").innerHTML = JSON.stringify(data, undefined, 2);