Device Memory API

The capabilities of a client device largely depend on the amount of available RAM. Traditionally, developers had to use heuristics and either benchmark a device or infer device capabilities based on other factors like the device manufacturer or User Agent strings.

There are two ways to determine the approximate amount of RAM a device has: use the Device Memory JavaScript API or accept Client Hints.

You may query the approximate amount of RAM a device has by retrieving Navigator.deviceMemory or WorkerNavigator.deviceMemory.

const RAM = navigator.deviceMemory;

You may also use the Client Hints HTTP Header with the Device-Memory directive to retrieve the same approximate RAM capacity.

Navigator.deviceMemory Read only

Returns the approximate amount of device memory in gigabytes.

WorkerNavigator.deviceMemory Read only

Returns the approximate amount of device memory in gigabytes.

• Device-Memory header