Amazon GuardDuty Tester vs Leonidas: Side-by-Side Comparison (2026)
Features, pricing, ratings, and pros & cons — compared head-to-head.
Amazon GuardDuty Tester is a free threat simulation tool. Leonidas is a free threat simulation tool. Compare features, ratings, integrations, and community reviews side by side to find the best threat simulation fit for your security stack.
CST VerdictBased on our analysis of available product data, here is our conclusion:
AWS security teams evaluating GuardDuty need to validate that its detections actually fire in their environment before incidents do; Amazon GuardDuty Tester cuts through sandbox testing by injecting real proof-of-concept findings directly into your account at no cost. The 408 GitHub stars reflect its adoption among teams that discovered their GuardDuty tuning was silencing critical alerts. Skip this if you're not running GuardDuty yet or if your detection validation workflow already includes threat simulation tools; this is purely about understanding what GuardDuty sees and what it misses in your specific setup.
Security teams building internal threat simulation programs on AWS or GCP will get the most from Leonidas because its YAML-based framework lets you define attacker procedures once and automatically generate executable code, detection rules, and documentation simultaneously, cutting your simulation development cycle by weeks. The 593 GitHub stars and active community contributions signal real adoption among cloud-native shops that prioritize repeatability over point-and-click simplicity. Skip this if your org needs a managed SaaS platform with guided scenarios and executive reporting; Leonidas assumes you're engineering-heavy and comfortable maintaining your own TTP library.
