Solved: EC2 Cost Optimization

🚀 Executive Summary TL;DR: Unmanaged EC2 instances often lead to unexpected AWS costs due to forgotten resources and poor visibility. This guide provides strategies ranging from immediate CLI termination of untagged instances to automated lifecycle management via tagging and Lambda, and even a drastic aws-nuke for full account resets. 🎯 Key Takeaways Manual CLI commands, specifically aws ec2 describe-instances and aws ec2 terminate-instances , can be used for an emergency ‘Find and Destroy’ blitz to stop untagged, running EC2 instances and prevent immediate cost escalation. Implementing a strict tagging policy (e.g., owner , project , ttl-hours ) combined with a scheduled Lambda function allows for automated termination of expired EC2 instances, creating a self-cleaning cloud environment. For non-critical, ephemeral accounts, aws-nuke offers a powerful, high-risk method to programmatically delete all resources except those explicitly whitelisted, effectively resetting the account to a