Crypto

The Crypto interface represents basic cryptography features available in the current context. It allows access to a cryptographically strong random number generator and to cryptographic primitives.

Note: This feature is available in Web Workers.

The Web Crypto API is accessed through the Window.crypto property, which is a Crypto object.

Properties

This interface implements properties defined on RandomSource.

Crypto.subtle Read only Secure context
Returns a SubtleCrypto object providing access to common cryptographic primitives, like hashing, signing, encryption, or decryption.

Methods

This interface implements methods defined on RandomSource.

Crypto.getRandomValues()
Fills the passed TypedArray with cryptographically sound random values.

Usage notes

You should avoid using the Web Crypto API on insecure contexts, even though the Crypto interface is present on insecure contexts, as is the Window.crypto property. In addition, the Crypto method getRandomValues() is available on insecure contexts, but the subtle property is not.

In general, you probably should just treat Crypto as available only on secure contexts.

Specifications

Specification Status Comment
Web Cryptography API
The definition of 'Crypto' in that specification.
Recommendation Initial definition

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
CryptoChrome Full support 11Edge Full support 12Firefox Full support 26IE Full support 11Opera Full support 15Safari Full support 6.1WebView Android Full support YesChrome Android Full support 18Firefox Android Full support 26Opera Android Full support 14Safari iOS Full support 6.1Samsung Internet Android Full support 1.0
getRandomValues()Chrome Full support 11Edge Full support 12Firefox Full support 26IE Full support 11Opera Full support 15Safari Full support 6.1WebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 26Opera Android Full support 14Safari iOS Full support 6.1Samsung Internet Android Full support 1.0
subtle
Experimental
Chrome Full support 37Edge Full support 12Firefox Full support 34
Full support 34
No support 32 — 34
Disabled
Disabled From version 32 until version 34 (exclusive): this feature is behind the dom.webcrypto.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.
IE Partial support 11Opera Full support 24Safari Full support 10.1
Full support 10.1
Full support 7
Prefixed
Prefixed Implemented with the vendor prefix: webkit
WebView Android Full support 37Chrome Android Full support 37Firefox Android Full support 34
Full support 34
No support 32 — 34
Disabled
Disabled From version 32 until version 34 (exclusive): this feature is behind the dom.webcrypto.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.
Opera Android Full support 24Safari iOS Full support 10.3
Full support 10.3
Full support 7
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Samsung Internet Android Full support 3.0

Legend

Full support
Full support
Partial support
Partial support
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
User must explicitly enable this feature.
User must explicitly enable this feature.
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

See also