Set.prototype.add()
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 add()
method of Set
instances inserts a new element with a specified value in to this set, if there isn't an element with the same value already in this set
Try it
const set1 = new Set();
set1.add(42);
set1.add(42);
set1.add(13);
for (const item of set1) {
console.log(item);
// Expected output: 42
// Expected output: 13
}
Syntax
js
add(value)
Parameters
value
-
The value of the element to add to the
Set
object.
Return value
The Set
object with added value.
Examples
Using the add() method
js
const mySet = new Set();
mySet.add(1);
mySet.add(5).add("some text"); // chainable
console.log(mySet);
// Set [1, 5, "some text"]
Specifications
Specification |
---|
ECMAScript® 2025 Language Specification # sec-set.prototype.add |
Browser compatibility
Report problems with this compatibility data on GitHubdesktop | mobile | server | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
add |
Legend
Tip: you can click/tap on a cell for more information.
- Full support
- Full support
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.