Comparison Parameter AWS CloudTrail AWS CloudWatch
Primary Purpose Tracks API activity and records AWS account actions Monitors system health, application logs, and metrics
Type of Data Collected API events, user actions, configuration changes Performance metrics, logs, alarms, and custom events
Real-time Monitoring No (Captures logs after an event occurs) Yes (Continuously tracks performance & logs)
Data Retention 90 days by default (Extended retention in S3) 15 days by default (Configurable)
Security & Compliance Assists in audits for GDPR, HIPAA, PCI-DSS compliance Enhances application security by detecting anomalies
Visualization & Dashboards No built-in UI for visualization Provides real-time dashboards & anomaly detection
Integration with AWS Services Works with S3, Lambda, SNS for security automation Integrates with EC2, RDS, Lambda, Auto Scaling & more
Costing Model Free basic logging; Advanced features incur charges Pay-as-you-go based on log volume & queries
Alerting & Notifications No built-in alerts Supports alarms & automated notifications
Multi-Region Support Yes (Monitors activity across multiple AWS regions) Yes (Aggregates metrics from different regions)
Anomaly Detection CloudTrail Insights detects unusual API activity Uses ML-based anomaly detection for metrics & logs
Custom Metrics Support No support for defining custom metrics Allows users to create custom metrics for monitoring
Best For Security audits, compliance tracking, and governance Performance monitoring, troubleshooting, and automation