AWS Cost Foundations

Practical AWS FinOps guides for engineers, architects, finance teams, and cloud leaders. Start with the fundamentals. Build from evidence.

Series: AWS Cost Foundations

announcement · 2026-07-13

Mean Time to Explanation: A New Metric for AWS Cost Investigation

Operations teams track MTTR and MTTI. FinOps teams should track MTTE: the time from cost signal or question to defensible explanation. Introducing the metric and how Kulshan helps reduce it.

explainer · 2026-06-25

EC2-Other is hiding your real problem.

Your top Cost Explorer line item says EC2-Other. That is not a service. That is a junk drawer. Here is what is inside it, why NAT Gateway is the usual culprit, and the fix that costs zero dollars.

field guide · 2026-06-20

CUR 2.0 vs FOCUS: Which AWS Billing Export Should You Enable First?

CUR is for AWS investigation. FOCUS is for standardization. Which export to enable first, and why mature FinOps teams often use both.

field guide · 2026-06-19

Enable AWS Data Exports (CUR 2.0)

Get raw billing data flowing to S3. The dataset every FinOps tool, consultant, and analyst eventually relies on. Step-by-step with screenshots.

workflow · 2026-06-18

Cost Explorer first, the bill second.

The workflow I run on every AWS account I audit, and why the service-level bill view hides the things that matter.

field notes · 2026-06-04

The $40,000 NAT Gateway nobody noticed.

A field note about NAT Gateway data processing charges hiding inside EC2-Other, and the three things to check first on any AWS account.