Cost Optimization & FinOps
Part 3
palaniappan p 7 min
AWS KMS Pricing: Why a $1/Month Key Can Generate a $4,000/Month Bill
KMS keys cost $1/month each — the easy number. The hidden bill is request volume at $0.03 per 10K calls, multi-region replicas that each bill $1/month independently, and asymmetric operations at 5× the symmetric rate. An S3 bucket with 100M SSE-KMS objects and an active read pattern can generate thousands per month in KMS requests alone.