JSFiddle - React, Tailwind, and code Playground

JavaScript

var jsonObj = [{"key1": "value1", "key2": "value2", "key3": "value3" }, {"key1": "value1", "key2": "value2", "key3": "value3" }];

$.each(jsonObj, function(i){
	$.each(jsonObj[i], function(key){
  	jsonObj[i][key] = "changed" + key; 
  });
});

console.log(jsonObj);