AWS Key Management Service (KMS)
Encryption key management software
Data security software
- Features
- Ease of use
- Ease of management
- Quality of support
- Affordability
- Market presence
Take the quiz to check if AWS Key Management Service (KMS) and its alternatives fit your requirements.
$1.00 per month per KMS key
Free Trial unavailable
Free version
Small
Medium
Large
- Retail and wholesale
- Accommodation and food services
- Arts, entertainment, and recreation
What is AWS Key Management Service (KMS)
AWS Key Management Service (KMS) is a managed service for creating, storing, and controlling access to cryptographic keys used to encrypt data. It is primarily used by teams building on AWS that need centralized key administration, access controls, and auditability for encryption across AWS services and applications. KMS integrates with AWS Identity and Access Management (IAM), AWS CloudTrail, and many AWS-native encryption features, and supports both AWS-owned and customer-managed keys, including keys backed by hardware security modules (HSMs).
Deep AWS service integration
KMS integrates broadly with AWS services that support encryption at rest and in transit, enabling consistent key usage across storage, databases, messaging, and compute workflows. This reduces the need to build custom key distribution and rotation mechanisms for AWS-native services. It also supports envelope encryption patterns commonly used in cloud applications.
Centralized access control and audit
KMS uses IAM policies and key policies to control who can administer keys and who can use them for cryptographic operations. It logs key usage events through AWS CloudTrail, supporting security monitoring and compliance evidence collection. These controls are managed centrally rather than embedded separately in each application.
Managed lifecycle and HSM backing
KMS provides managed key creation, rotation options, and deletion scheduling, reducing operational overhead compared to self-managed key infrastructure. Customer-managed keys can be backed by AWS-managed HSMs, and KMS also supports integration with AWS CloudHSM for dedicated HSM use cases. This helps organizations meet requirements for hardware-backed key protection without operating HSM hardware directly.
Strong AWS platform dependency
KMS is designed primarily for AWS workloads and AWS service integrations. Organizations with significant multi-cloud or on-premises encryption key management needs may require additional tooling or separate key management systems. Migrating applications away from AWS can require reworking encryption and key access patterns.
Policy model can be complex
Effective administration often requires understanding both IAM policies and KMS key policies, plus service-specific permissions for integrated AWS services. Misconfigurations can lead to denied access or overly broad permissions that increase risk. Large environments may need careful governance and standardized policy templates.
Costs scale with key operations
KMS pricing typically includes per-key charges and per-request charges for cryptographic operations, which can become material for high-throughput applications. Some use cases may need architectural patterns (such as caching data keys) to reduce request volume. Budgeting can be harder when encryption calls scale with application traffic.
Plan & Pricing
Pricing model: Pay-as-you-go Free tier/trial: Free tier — 20,000 requests/month (calculated across all Regions). Requests that reference asymmetric KMS keys (GenerateDataKeyPair, GenerateDataKeyPairWithoutPlaintext, Sign, Verify, Encrypt, Decrypt, GetPublicKey) are excluded from the free tier. Example costs:
- KMS key (customer managed): $1.00 per KMS key per month (prorated hourly).
- API requests (many common operations): $0.03 per 10,000 requests.
- Asymmetric / signing requests (example shown on site): $0.15 per 10,000 requests.
- When using AWS CloudHSM (custom key store) CloudHSM charges apply (example on site uses $1.60 per HSM per hour). Notes & key details:
- The $1/month key storage charge applies to symmetric, asymmetric, HMAC, multi-Region (primary and replica counted separately), keys with imported key material, and keys with origin in CloudHSM or an external key store (XKS).
- There is no monthly charge for AWS-managed or AWS-owned KMS keys; creation/storage of those is not charged, though API requests against them are charged.
- The first and second rotation of a KMS key (automatic or on-demand) adds $1/month (prorated hourly); rotations after the second are not billed.
- CloudHSM and XKS-related charges are separate and subject to their own pricing. Discount options: Not specified on the KMS pricing page; AWS offers "Get pricing assistance" / contact sales for personalized quotes.
Seller details
Amazon Web Services, Inc.
Seattle, Washington, USA
2006
Subsidiary
https://aws.amazon.com/
https://x.com/awscloud
https://www.linkedin.com/company/amazon-web-services/
