The SubtleCrypto.wrapKey() method returns a Promise of a wrapped symmetric key for usage (transfer, storage) in unsecure environments. The wrapped buffer returned is in the format given in parameters, and contains the key wrapped by the given wrapping key with the given algorithm.


var result = crypto.subtle.wrapKey(format, key, wrappingKey, wrapAlgo);


  • format is an enumerated value describing the data format in which the key must be wrapped. It can be one of the following:
  • key is the CryptoKey to wrap.
  • wrappingkey is the CryptoKey used to perform the wrapping.
  • wrapAlgo is the DOMString} representing the algorithm used to perform the wrapping. It is one of the following: AES-CBC, AES-CTR, AES-GCM, RSA-OAEP, and AES-KW.

Return value

  • result is a Promise that returns the wrapped key in the requested format.


The promise is rejected when one of the following exceptions is encountered:

  • InvalidAccessError when the wrapping key is not a key for the requested wrap algorithm.
  • NotSupported when trying to use an algorithm that is either unknown or isn't suitable for encryption or wrapping.
  • TypeError when trying to use an invalid format.


Specification Status Comment
Web Cryptography API
The definition of 'SubtleCrypto.wrapKey()' in that specification.
Recommendation Initial definition.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support37123411248
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support5353 ?3437 ?6.0

See also

Document Tags and Contributors

Contributors to this page: kgeorgiou, fscholz, Dans24, abbycar, teoli
Last updated by: kgeorgiou,