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---
title: Map.prototype.get()
slug: Web/JavaScript/Reference/Global_Objects/Map/get
page-type: javascript-instance-method
browser-compat: javascript.builtins.Map.get
---
{{JSRef}}
The **`get()`** method of {{jsxref("Map")}} instances returns a specified element from this map. If the
value that is associated to the provided key is an object, then you will get a
reference to that object and any change made to that object will effectively
modify it inside the `Map` object.
{{EmbedInteractiveExample("pages/js/map-prototype-get.html")}}
## Syntax
```js-nolint
get(key)
```
### Parameters
- `key`
- : The key of the element to return from the `Map` object.
### Return value
The element associated with the specified key, or
{{jsxref("undefined")}} if the key can't be found in the `Map` object.
## Examples
### Using get()
```js
const myMap = new Map();
myMap.set("bar", "foo");
console.log(myMap.get("bar")); // Returns "foo"
console.log(myMap.get("baz")); // Returns undefined
```
### Using get() to retrieve a reference to an object
```js
const arr = [];
const myMap = new Map();
myMap.set("bar", arr);
myMap.get("bar").push("foo");
console.log(arr); // ["foo"]
console.log(myMap.get("bar")); // ["foo"]
```
Note that the map holding a reference to the original object effectively means the object cannot be garbage-collected, which may lead to unexpected memory issues. If you want the object stored in the map to have the same lifespan as the original one, consider using a {{jsxref("WeakMap")}}.
## Specifications
{{Specifications}}
## Browser compatibility
{{Compat}}
## See also
- {{jsxref("Map")}}
- {{jsxref("Map.prototype.set()")}}
- {{jsxref("Map.prototype.has()")}}