cloudcostdown.euAWS Cost Explorer · Getting Started Guide
How to Use AWS Cost Explorer: Step-by-Step Guide
AWS Cost Explorer is free and more powerful than most teams realize. This guide shows the most useful views for finding cost drivers, identifying waste, and tracking optimization progress.
4 Essential Cost Explorer Views
Monthly cost by service
Steps
- Cost Explorer → Monthly spend by service (default view on open)
- Change date range to Last 6 months
- Look for services trending upward - which are growing faster than your business?
- Click any bar to drill down to that service's usage types
Insight: This view shows you the 3–5 services that make up 80% of your bill. Start optimization there.
Daily spend by usage type
Steps
- Cost Explorer → Group by: Usage Type → Daily granularity
- Look for unexpected spikes on specific days (deployment day? data pipeline run?)
- Identify which usage types are consistently high vs. occasionally spiky
- Usage types map directly to billable resources: DataTransfer-Out-Bytes, BoxUsage:m5.xlarge, etc.
Insight: Daily granularity reveals patterns: weekend spikes from batch jobs, deployment day cost increases, or data transfer patterns from scheduled processes.
Cost by tag (team/service)
Steps
- Cost Explorer → Group by: Tag → select your tag key (e.g., team)
- This shows cost per team or service - requires cost allocation tags to be activated first
- Filter to a specific service to see which teams are driving that service's cost
- Export to CSV for monthly cost reporting
Insight: Tag-based views only work if your resources are tagged and the tags are activated as Cost Allocation Tags in Billing settings.
Reserved Instance and Savings Plans utilization
Steps
- Cost Explorer → Savings Plans → Utilization report
- Look for Savings Plans with utilization below 80% - you're paying for committed spend you're not using
- Cost Explorer → Reserved Instances → Utilization report - same check for RIs
- Unused commitment = money wasted on a discount that isn't being applied
Insight: Over-buying Savings Plans or Reserved Instances is wasteful. Under-buying means you're paying full price. Utilization > 90% is the target.
Frequently Asked Questions
Is AWS Cost Explorer free?
The Cost Explorer UI is free. The API costs $0.01 per request - relevant if you programmatically query Cost Explorer data (e.g., for custom dashboards). All standard console views, reports, and recommendations are free.
How far back does Cost Explorer data go?
Cost Explorer stores up to 13 months of cost and usage data. You can analyze trends, compare month-over-month, and export historical data going back over a year. Hourly granularity is available for the last 14 days.
What is the difference between Cost Explorer and the Billing dashboard?
The Billing dashboard shows your current month's charges by service - a simple summary. Cost Explorer is a full analytics tool: time-series charts, custom date ranges, grouping by tag/service/region/account, filtering, rightsizing recommendations, and RI/Savings Plans reports.
Can Cost Explorer show me cost per EC2 instance?
Not directly by instance ID - Cost Explorer groups by service and usage type. For per-instance cost visibility, use Cost Allocation Tags (tag each instance with a unique service=name tag) or use AWS Compute Optimizer for per-instance rightsizing analysis.
How do I set up cost alerts in Cost Explorer?
Cost Explorer doesn't create alerts directly. Use AWS Budgets (linked from Cost Explorer) to set monthly spend thresholds with email/SNS alerts, or use AWS Cost Anomaly Detection (free) for ML-based anomaly alerts. Both are accessible from the Cost Management console.