Third-party sites, not ours. Links checked 2026-10-16.
- TheLineman subnet practice: quick drills.
- SubnetCalc practice: practice alongside a calculator.
- CIDRtools quiz: CIDR-focused quizzes.
- ITInsightHub subnetting practice: another practice set.
- Hack the Route tools: a collection of networking tools.
Know a better one? Tell us.