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Set.prototype.clear() - JavaScript | MDN

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Set.prototype.clear()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The clear() method of Set instances removes all elements from this set.

In this article

Try it

const set = new Set();
set.add(1);
set.add("foo");

console.log(set.size);
// Expected output: 2

set.clear();

console.log(set.size);
// Expected output: 0

Syntax

js

clear()

Parameters

None.

Return value

None (undefined).

Examples

Using the clear() method

js
const mySet = new Set();
mySet.add(1);
mySet.add("foo");

console.log(mySet.size); // 2
console.log(mySet.has("foo")); // true

mySet.clear();

console.log(mySet.size); // 0
console.log(mySet.has("foo")); // false

Specifications

Specification

ECMAScript® 2027 Language Specification
# sec-set.prototype.clear

Browser compatibility

Enable JavaScript to view this browser compatibility table.

See also

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This page was last modified on Jul 20, 2025 by MDN contributors.

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Standard built-in objects
Set
Constructor
1. Set()
Static properties
1. [Symbol.species]
Instance methods
Instance properties
1. size
Inheritance
Object/Function
Static methods
Static properties
Instance methods
Instance properties
1. __proto__
2. constructor