DescribeKey - Amazon Key Management Service
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China.


Provides detailed information about a KMS key. You can run DescribeKey on a customer managed key or an Amazon managed key.

This detailed information includes the key ARN, creation date (and deletion date, if applicable), the key state, and the origin and expiration date (if any) of the key material. It includes fields, like KeySpec, that help you distinguish symmetric from asymmetric KMS keys. It also provides information that is particularly important to asymmetric keys, such as the key usage (encryption or signing) and the encryption algorithms or signing algorithms that the KMS key supports. For KMS keys in custom key stores, it includes information about the custom key store, such as the key store ID and the Amazon CloudHSM cluster ID. For multi-Region keys, it displays the primary key and all related replica keys.

DescribeKey does not return the following information:

In general, DescribeKey is a non-mutating operation. It returns data about KMS keys, but doesn't change them. However, Amazon services use DescribeKey to create Amazon managed keys from a predefined Amazon alias with no key ID.

Cross-account use: Yes. To perform this operation with a KMS key in a different Amazon Web Services account, specify the key ARN or alias ARN in the value of the KeyId parameter.

Required permissions: kms:DescribeKey (key policy)

Related operations:

Request Syntax

{ "GrantTokens": [ "string" ], "KeyId": "string" }

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.


In the following list, the required parameters are described first.


Describes the specified KMS key.

If you specify a predefined Amazon alias (an Amazon alias with no key ID), Amazon KMS associates the alias with an Amazon managed key and returns its KeyId and Arn in the response.

To specify a KMS key, use its key ID, key ARN, alias name, or alias ARN. When using an alias name, prefix it with "alias/". To specify a KMS key in a different Amazon Web Services account, you must use the key ARN or alias ARN.

For example:

  • Key ID: 1234abcd-12ab-34cd-56ef-1234567890ab

  • Key ARN: arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab

  • Alias name: alias/ExampleAlias

  • Alias ARN: arn:aws:kms:us-east-2:111122223333:alias/ExampleAlias

To get the key ID and key ARN for a KMS key, use ListKeys or DescribeKey . To get the alias name and alias ARN, use ListAliases .

Type: String

Length Constraints: Minimum length of 1. Maximum length of 2048.

Required: Yes


A list of grant tokens.

Use a grant token when your permission to call this operation comes from a new grant that has not yet achieved eventual consistency. For more information, see Grant token and Using a grant token in the Amazon Key Management Service Developer Guide.

Type: Array of strings

Array Members: Minimum number of 0 items. Maximum number of 10 items.

Length Constraints: Minimum length of 1. Maximum length of 8192.

Required: No

Response Syntax

{ "KeyMetadata": { "Arn": "string", "AWSAccountId": "string", "CloudHsmClusterId": "string", "CreationDate": number, "CustomerMasterKeySpec": "string", "CustomKeyStoreId": "string", "DeletionDate": number, "Description": "string", "Enabled": boolean, "EncryptionAlgorithms": [ "string" ], "ExpirationModel": "string", "KeyId": "string", "KeyManager": "string", "KeySpec": "string", "KeyState": "string", "KeyUsage": "string", "MultiRegion": boolean, "MultiRegionConfiguration": { "MultiRegionKeyType": "string", "PrimaryKey": { "Arn": "string", "Region": "string" }, "ReplicaKeys": [ { "Arn": "string", "Region": "string" } ] }, "Origin": "string", "PendingDeletionWindowInDays": number, "SigningAlgorithms": [ "string" ], "ValidTo": number } }

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.


Metadata associated with the key.

Type: KeyMetadata object


For information about the errors that are common to all actions, see Common Errors.


The system timed out while trying to fulfill the request. The request can be retried.

HTTP Status Code: 500


The request was rejected because a specified ARN, or an ARN in a key policy, is not valid.

HTTP Status Code: 400


The request was rejected because an internal exception occurred. The request can be retried.

HTTP Status Code: 500


The request was rejected because the specified entity or resource could not be found.

HTTP Status Code: 400


The following examples are formatted for legibility.

Example Request

This example illustrates one usage of DescribeKey.

POST / HTTP/1.1 Host: Content-Length: 49 X-Amz-Target: TrentService.DescribeKey X-Amz-Date: 20170705T211529Z Authorization: AWS4-HMAC-SHA256\ Credential=AKIAI44QH8DHBEXAMPLE/20170705/us-east-2/kms/aws4_request,\ SignedHeaders=content-type;host;x-amz-date;x-amz-target,\ Signature=6bcb6a5ef9ee7585d83955e8a5c3f6d47cf581596208fc0e436fa1de26ef3f6a Content-Type: application/x-amz-json-1.1 {"KeyId": "1234abcd-12ab-34cd-56ef-1234567890ab"}

Example Response

This example illustrates one usage of DescribeKey.

HTTP/1.1 200 OK Server: Server Date: Wed, 05 Jul 2017 21:15:30 GMT Content-Type: application/x-amz-json-1.1 Content-Length: 335 Connection: keep-alive x-amzn-RequestId: 13230ddb-61c7-11e7-af6f-c5b105d7a982 { "KeyMetadata": { "AWSAccountId": "111122223333", "Arn": "arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab", "CreationDate": 1.499288695918E9, "CustomerMasterKeySpec": "SYMMETRIC_DEFAULT", "Description": "", "Enabled": true, "KeyId": "1234abcd-12ab-34cd-56ef-1234567890ab", "KeyManager": "CUSTOMER", "KeySpec": "SYMMETRIC_DEFAULT", "KeyState": "Enabled", "KeyUsage": "ENCRYPT_DECRYPT", "MultiRegion": false, "Origin": "AWS_KMS", "EncryptionAlgorithms": [ "SYMMETRIC_DEFAULT" ] } }

See Also

For more information about using this API in one of the language-specific Amazon SDKs, see the following: