JavaScript Object Methods – Complete List with Examples

These are called on Object itself (Object.keys(user)), not on your objects. Most work only with an object's own properties, not inherited ones.

Name	Description	Since
`Object.assign()`	Copy all own enumerable properties from one or more source objects into a target object, and return the target.	ES2015
`Object.create()`	Create a new object with the given prototype (or null for an object with no inherited properties at all).	ES5
`Object.defineProperty()`	Add or change one property with full control over whether it is writable, enumerable and configurable, or define a getter.	ES5
`Object.defineProperties()`	Add or change several properties at once using property descriptors, each with its own writable and enumerable flags.	ES5
`Object.entries()`	Return an array of an object's own enumerable [key, value] pairs, ready for for…of loops or array methods.	ES2017
`Object.freeze()`	Make an object immutable: no properties can be added, removed or changed. The freeze is shallow.	ES5
`Object.fromEntries()`	Build an object from an iterable of [key, value] pairs, such as an array or a Map. The opposite of Object.entries().	ES2019
`Object.getOwnPropertyDescriptor()`	Return the descriptor (value, writable, enumerable, configurable or get/set) of one own property.	ES5
`Object.getOwnPropertyNames()`	Return all own string property names, including non-enumerable ones that Object.keys() skips.	ES5
`Object.getPrototypeOf()`	Return the prototype of an object: the object it inherits methods and properties from, or null.	ES5
`Object.groupBy()`	Group the items of an iterable into an object whose keys come from a callback, e.g. orders grouped by status.	ES2024
`Object.hasOwn()`	Return true if an object has a property of its own (not inherited). The safer replacement for hasOwnProperty().	ES2022
`Object.is()`	Compare two values like === but treat NaN as equal to NaN and +0 as different from -0.	ES2015
`Object.isFrozen()`	Return true if an object is frozen: no properties can be added, removed or changed.	ES5
`Object.isSealed()`	Return true if an object is sealed: properties can't be added or removed, but existing ones may still change.	ES5
`Object.keys()`	Return an array of an object's own enumerable property names, in insertion order (integer keys first).	ES5
`Object.seal()`	Prevent adding or removing properties while still allowing existing properties to be changed.	ES5
`Object.setPrototypeOf()`	Change the prototype of an existing object. It is slow in most engines; prefer Object.create() or classes.	ES2015
`Object.values()`	Return an array of an object's own enumerable property values, in the same order as Object.keys().	ES2017

Name

Description

Since

Object.assign()

Copy all own enumerable properties from one or more source objects into a target object, and return the target.

ES2015

Object.create()

Create a new object with the given prototype (or null for an object with no inherited properties at all).

ES5

Object.defineProperty()

Add or change one property with full control over whether it is writable, enumerable and configurable, or define a getter.

ES5

Object.defineProperties()

Add or change several properties at once using property descriptors, each with its own writable and enumerable flags.

ES5

Object.entries()

Return an array of an object's own enumerable [key, value] pairs, ready for for…of loops or array methods.

ES2017

Object.freeze()

Make an object immutable: no properties can be added, removed or changed. The freeze is shallow.

ES5

Object.fromEntries()

Build an object from an iterable of [key, value] pairs, such as an array or a Map. The opposite of Object.entries().

ES2019

Object.getOwnPropertyDescriptor()

Return the descriptor (value, writable, enumerable, configurable or get/set) of one own property.

ES5

Object.getOwnPropertyNames()

Return all own string property names, including non-enumerable ones that Object.keys() skips.

ES5

Object.getPrototypeOf()

Return the prototype of an object: the object it inherits methods and properties from, or null.

ES5

Object.groupBy()

Group the items of an iterable into an object whose keys come from a callback, e.g. orders grouped by status.

ES2024

Object.hasOwn()

Return true if an object has a property of its own (not inherited). The safer replacement for hasOwnProperty().

ES2022

Object.is()

Compare two values like === but treat NaN as equal to NaN and +0 as different from -0.

ES2015

Object.isFrozen()

Return true if an object is frozen: no properties can be added, removed or changed.

ES5

Object.isSealed()

Return true if an object is sealed: properties can't be added or removed, but existing ones may still change.

ES5

Object.keys()

Return an array of an object's own enumerable property names, in insertion order (integer keys first).

ES5

Object.seal()

Prevent adding or removing properties while still allowing existing properties to be changed.

ES5

Object.setPrototypeOf()

Change the prototype of an existing object. It is slow in most engines; prefer Object.create() or classes.

ES2015

Object.values()

Return an array of an object's own enumerable property values, in the same order as Object.keys().

ES2017