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Encryption Cost Forecast

AWS KMS Pricing Calculator

Model customer-managed keys, API request volume, and multi-region replicas before SSE-KMS fan-out dominates the invoice.

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  • Instant results
  • ~2 min

Rates reviewed

Read the full breakdown AWS KMS Pricing covers billing dimensions, traps, and a 30-day cleanup plan.

Step 1 of 3 33%

Key inventory

us-east-1 list rates, pricing as of 2026-06-18. CloudHSM-backed keys and custom key store charges are excluded. Source: AWS public pricing .

Key ownership
keys

$1.00 per key per month.

regions

Each replica region bills $1/key/mo independently.

Who This Tool Is For

Security architects, platform engineers, and FinOps leads planning CMK strategy for regulated or high-volume AWS workloads.

Why We Built This Tool

KMS bills stack per-key storage ($1/mo) with per-10K API charges — high-fanout services multiply requests invisibly.

What Problem It Solves

  • CMK sprawl. Orphaned keys bill $1/mo each with zero requests.
  • Multi-region replicas. Each replica region multiplies key storage independently.
  • Asymmetric premium. RSA/ECDSA operations bill at 5× the symmetric rate.

Pair with our cloud security service or the S3 pricing calculator for SSE-KMS context.

Frequently Asked Questions

Where do these KMS prices come from?

Rates are AWS published us-east-1 list prices (AWS KMS pricing), pricing as of 2026-06-18.

Are AWS-managed keys free?

AWS-managed keys (alias starts with aws/) have no $1/month key charge. Request volume still bills at $0.03 per 10K symmetric calls, with 20,000 free requests per month per account.

How is multi-region key pricing different?

Each multi-region replica is billed as its own key — $1/month per replica per region. A key replicated to 5 regions costs $5/month in replica charges alone, plus the primary key.

Why is asymmetric KMS more expensive?

Asymmetric operations (RSA, ECDSA, ML-KEM) bill at $0.15 per 10K requests — 5× the $0.03 symmetric rate due to higher HSM compute cost.

How do S3 Bucket Keys affect my bill?

S3 Bucket Keys can reduce KMS request volume by up to 99% on SSE-KMS buckets by batching data key generation. Enable on every high-traffic SSE-KMS bucket.

Does this include CloudHSM?

No. Dedicated CloudHSM clusters bill separately (~$1.45/hour per HSM). This calculator covers standard KMS CMK storage and API requests only.

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