/Web APIs


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 global crypto property, which is a Crypto object.

Instance 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.

Instance methods

This interface implements methods defined on RandomSource.


Fills the passed TypedArray with cryptographically sound random values.


Returns a randomly generated, 36 character long v4 UUID.

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 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.


Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
Crypto 11 12 21 11 15 5 ≤37 18 21 14 5 1.0
getRandomValues 11 12 21 11 15 5 ≤37 18 21 14 5 1.0
randomUUID 92 92 95 No 78 15.4 92 92 95 65 15.4 16.0
subtle 37 12 34 11 24 117–11.1 37 37 34 24 117–11.3 3.0

See also

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