Secure context
This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The Device-Memory header is a Device Memory API header that works like Client Hints header which represents the approximate amount of RAM client device has.
| Header type | Request header |
|---|---|
| Forbidden header name | ? |
Note: Client Hints are accessible only on secure origins (via TLS). Server has to opt in to receive Device-Memory header from the client by sending Accept-CH and Accept-CH-Lifetime response headers.
Syntax
The amount of device RAM can be used as a fingerprinting variable, so values for the header are intentionally coarse to reduce the potential for its misuse. The header takes on the following values: 0.25, 0.5, 1, 2, 4, 8.
Device-Memory: <number>
Examples
Server first needs to opt in to receive Device-Memory header by sending the response headers Accept-CH containing Device-Memory and Accept-CH-Lifetime.
Accept-CH: Device-Memory Accept-CH-Lifetime: 86400
Then on subsequent requests the client might send Device-Memory header back:
Device-Memory: 1
Specifications
| Specification | Status | Comment |
|---|---|---|
| Device Memory 1 The definition of 'Device-Memory' in that specification. |
Editor's Draft | Initial definition. |
Browser compatibility
The compatibility table in 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.
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Device-Memory | Chrome Full support 61 | Edge ? | Firefox ? | IE ? | Opera Full support 48 | Safari ? | WebView Android Full support 61 | Chrome Android Full support 61 | Firefox Android ? | Opera Android ? | Safari iOS ? | Samsung Internet Android Full support 8.0 |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.