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  4. Standard built-in objects
  5. Set
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Set.prototype.keys()

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 keys() method of Set instances is an alias for the values() method.

In this article

Syntax

js
keys()

Parameters

None.

Return value

A new iterable iterator object.

Examples

Using keys()

The keys() method is exactly equivalent to the values() method.

js
const mySet = new Set(); mySet.add("foo"); mySet.add("bar"); mySet.add("baz"); const setIter = mySet.keys(); console.log(setIter.next().value); // "foo" console.log(setIter.next().value); // "bar" console.log(setIter.next().value); // "baz"

Specifications

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

Browser compatibility

Enable JavaScript to view this browser compatibility table.

See also

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This page was last modified on Jul 10, 2025 by MDN contributors.

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  1. Standard built-in objects
  2. Set
  3. Constructor
    1. Set()
  4. Static properties
    1. [Symbol.species]
  5. Instance methods
    1. add()
    2. clear()
    3. delete()
    4. difference()
    5. entries()
    6. forEach()
    7. has()
    8. intersection()
    9. isDisjointFrom()
    10. isSubsetOf()
    11. isSupersetOf()
    12. keys()
    13. symmetricDifference()
    14. union()
    15. values()
    16. [Symbol.iterator]()
  6. Instance properties
    1. size
  7. Inheritance
  8. Object/Function
  9. Static methods
    1. apply()
    2. bind()
    3. call()
    4. toString()
    5. [Symbol.hasInstance]()
  10. Static properties
    1. displayName
    2. length
    3. name
    4. prototype
    5. arguments
    6. caller
  11. Instance methods
    1. __defineGetter__()
    2. __defineSetter__()
    3. __lookupGetter__()
    4. __lookupSetter__()
    5. hasOwnProperty()
    6. isPrototypeOf()
    7. propertyIsEnumerable()
    8. toLocaleString()
    9. toString()
    10. valueOf()
  12. Instance properties
    1. __proto__
    2. constructor

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