The CSSNamespaceRule.namespaceURI read-only property returns a DOMString containing the text of the URI of the given namespace.


var namespaceURI = CSSNamespaceRule.namespaceURI


A DOMString containing a URI.


Specification Status Comment
CSS Object Model (CSSOM)
The definition of 'namespaceURI' in that specification.
Working Draft Initial definition.

Browser compatibility

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ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 47Edge Full support 12Firefox Full support 59IE No support NoOpera Full support 36Safari ? WebView Android Full support 47Chrome Android Full support 47Edge Mobile Full support YesFirefox Android Full support 59Opera Android Full support 36Safari iOS ? Samsung Internet Android Full support 5.0


Full support  
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Compatibility unknown  
Compatibility unknown

Document Tags and Contributors

Contributors to this page: fscholz, chrisdavidmills, erikadoyle, rolfedh, jpmedley
Last updated by: fscholz,