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RandomSource represents a source of cryptographically secure random numbers. It is available via the Crypto object of the global object: Window.crypto on Web pages, WorkerGlobalScope.crypto in workers.

RandomSource is a not an interface and no object of this type can be created.


RandomSource neither defines nor inherits any property.


Fills the passed ArrayBufferView with cryptographically sound random values.


Specification Status Comment
Web Cryptography API Candidate Recommendation Initial definition

Browser Compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 11.0 WebKit bug 22049 (Yes) 21 (21) [1] 11.0 15.0 3.1
Feature Android Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support 23 (Yes) 21.0 (21) No support No support 6

[1] Although the transparent RandomSource is only available since Firefox 26, the feature was available in Firefox 21.

See also

Document Tags and Contributors

 Contributors to this page: abbycar, Jeremie, AMcBain, teoli
 Last updated by: abbycar,