Screen.mozBrightness

Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

Deprecated
This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

Indicates how bright the screen's backlight is, on a scale from 0 (very dim) to 1 (full brightness); this value is a double-precision float.

You can read and write this attribute even when the screen is disabled, but the backlight is off while the screen is disabled. If you write a value of X into this attribute, the attribute may not have the same value X when you later read it. Most screens don't support as many different brightness levels as there are doubles between 0 and 1. The value's precision might be reduced before storing it.

Syntax

let screenBrightness = window.screen.mozBrightness;

Specifications

Not part of specification.

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
mozBrightness
DeprecatedNon-standard
Chrome No support NoEdge No support NoFirefox Full support 12
Disabled
Full support 12
Disabled
Disabled From version 12: this feature is behind the dom.screenBrightnessProperty.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.
IE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoFirefox Android Full support 14
Disabled
Full support 14
Disabled
Disabled From version 14: this feature is behind the dom.screenBrightnessProperty.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.
Opera Android No support NoSafari iOS No support NoSamsung Internet Android No support No

Legend

Full support
Full support
No support
No support
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.
Deprecated. Not for use in new websites.
User must explicitly enable this feature.
User must explicitly enable this feature.