let obj = { name: { fName: 'Tony', lName: 'Stark', weaponNames: ['Lasers','Pulse Bolts','Energy Blade','Repulsor Rays'] }, age: 55, friends: [ { name: 'Peter Parker', character: 'Spider Man' }, { name: 'Bruce Banner', character: 'Hulk' }, ] }; let clone = Object.assign({},obj); clone.name.weaponNames = ['Unibeam','Smart Missiles']; clone.friends = [ { name: 'Steve Rogers', character: 'Captain America' }, { name: 'Natasha Romanoff', character: 'Black Widow' }, { name: 'Clint Barton', character: 'Hawkeye' }, ]; console.log(JSON.stringify(obj, null, 2)); console.log(JSON.stringify(clone, null, 2));