By continuing to use the platform, you accept the terms of the Privacy Policy and the use of cookies.

How to Copy an Object in JavaScript: Shallow vs Deep Copy

In JavaScript, object copying can be:

Shallow copy — only top-level properties are copied, nested objects are copied by reference.
Deep copy — a complete independent copy is created, including nested objects and arrays.

Shallow Copying

const obj = { name: "Alice", age: 25 };
const copy = { ...obj };

const obj = { name: "Bob" };
const copy = Object.assign({}, obj);

const original = { user: { name: "Tom" } };
const deepCopy = JSON.parse(JSON.stringify(original));

const deepCopy = structuredClone(obj);

import cloneDeep from 'lodash/cloneDeep';

const deepCopy = cloneDeep(obj);

Important:

Simple reference copying (const copy = obj) doesn't create a new object — it's a reference to the same object in memory.

Back

Forward